diff --git a/PDP10/pdp10_defs.h b/PDP10/pdp10_defs.h
index cc2fd9f3..e2014a76 100644
--- a/PDP10/pdp10_defs.h
+++ b/PDP10/pdp10_defs.h
@@ -779,7 +779,7 @@ t_stat show_addr (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat set_vec (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat show_vec (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat show_vec_mux (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat auto_config (char *name, int32 num);
+t_stat auto_config (const char *name, int32 num);
 
 
 #endif
diff --git a/PDP10/pdp10_ksio.c b/PDP10/pdp10_ksio.c
index 7c7517bc..df865df9 100644
--- a/PDP10/pdp10_ksio.c
+++ b/PDP10/pdp10_ksio.c
@@ -2212,7 +2212,7 @@ AUTO_CON auto_tab[] = {/*c  #v  am vm  fxa   fxv */
 #define DEV_NEXUS 0
 #endif
 #endif
-t_stat auto_config (char *name, int32 nctrl)
+t_stat auto_config (const char *name, int32 nctrl)
 {
 uint32 csr = IOPAGEBASE + AUTO_CSRBASE;
 uint32 vec = VEC_Q + AUTO_VECBASE;
diff --git a/PDP10/pdp10_lp20.c b/PDP10/pdp10_lp20.c
index 36b7db1f..b237a767 100644
--- a/PDP10/pdp10_lp20.c
+++ b/PDP10/pdp10_lp20.c
@@ -218,8 +218,8 @@ static void update_lpcs (int32 flg);
 static void change_rdy (int32 setrdy, int32 clrrdy);
 static int16 evenbits (int16 value);
 static t_stat lp20_help (FILE *st, struct sim_device *dptr,
-                            struct sim_unit *uptr, int32 flag, char *cptr); 
-static char *lp20_description (DEVICE *dptr); 
+                            struct sim_unit *uptr, int32 flag, const char *cptr); 
+static const char *lp20_description (DEVICE *dptr); 
 
 /* DEC standard VFU tape for 'optical' VFU default.
  * Note that this must be <= DV_SIZE as we copy it into the DAVFU.
@@ -1279,7 +1279,7 @@ return SCPE_OK;
 }
 
 static t_stat lp20_help (FILE *st, struct sim_device *dptr,
-                            struct sim_unit *uptr, int32 flag, char *cptr)
+                            struct sim_unit *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, 
          "The LP20 DMA line printer controller is a UNIBUS device developed by the 36-bit product line.\n"
@@ -1320,7 +1320,7 @@ fprintf (st,
 
 return SCPE_OK;
 }
-static char *lp20_description (DEVICE *dptr)
+static const char *lp20_description (DEVICE *dptr)
 {
     return "DMA Line Printer controller";
 }
diff --git a/PDP11/pdp11_cpumod.h b/PDP11/pdp11_cpumod.h
index ba8fb178..99d5f51a 100644
--- a/PDP11/pdp11_cpumod.h
+++ b/PDP11/pdp11_cpumod.h
@@ -267,7 +267,7 @@
 /* Data tables */
 
 struct cpu_table {
-    char                *name;                          /* model name */
+    const char          *name;                          /* model name */
     uint32              std;                            /* standard flags */
     uint32              opt;                            /* set/clear flags */
     uint32              maxm;                           /* max memory */
diff --git a/PDP11/pdp11_cr.c b/PDP11/pdp11_cr.c
index 439bd9e3..fd3aa07b 100644
--- a/PDP11/pdp11_cr.c
+++ b/PDP11/pdp11_cr.c
@@ -389,7 +389,7 @@ extern int32 int_req[IPL_HLVL];
 #define    BLOW_STOP        (3)                         /* shutting down */
 
 /* Card Reader state */
-static char     *cardFormat = "unknown";
+static const char *cardFormat = "unknown";
 static t_bool   (*readRtn)(UNIT *, int16 *, char *, char *);
 static char     ascii_code[4096];                       /* 2^12 possible values */
 static int      currCol;                                /* current column when reading */
@@ -440,7 +440,6 @@ static int32    cddb = 0;                               /* data, 2nd status */
 static int32    cddbs = 0;                              /* second status bits (or with cddb) */
 
 /* forward references */
-DEVICE cr_dev;
 static void setupCardFile (UNIT *, int32);
 t_stat cr_rd (int32 *, int32, int32);
 t_stat cr_wr (int32, int32, int32);
@@ -460,8 +459,8 @@ t_stat cr_set_eof (UNIT *, int32, char *, void *);
 t_stat cr_show_eof (FILE *, UNIT *, int32, void *);
 t_stat cr_set_trans (UNIT *, int32, char*, void *);
 t_stat cr_show_trans (FILE *, UNIT *, int32, void *);
-static t_stat cr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *cr_description (DEVICE *dptr);
+static t_stat cr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *cr_description (DEVICE *dptr);
 
 
 /* CR data structures
@@ -1796,7 +1795,7 @@ if (bits)
 return;
 }
 
-static t_stat cr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+static t_stat cr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 char devtype[MAXDESCRIP];
 int32 crtypes;
@@ -1939,7 +1938,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *cr_description (DEVICE *dptr)
+const char *cr_description (DEVICE *dptr)
 {
   /* Not thread-safe, but malloc() would be leak. */
   static char desc[MAXDESCRIP+sizeof(" card reader")-1] = "";
diff --git a/PDP11/pdp11_dc.c b/PDP11/pdp11_dc.c
index 746c1906..29c8e10c 100644
--- a/PDP11/pdp11_dc.c
+++ b/PDP11/pdp11_dc.c
@@ -141,8 +141,8 @@ void dco_clr_int (int32 ln);
 void dco_set_int (int32 ln);
 int32 dco_iack (void);
 void dcx_reset_ln (int32 ln);
-t_stat dcx_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *dcx_description (DEVICE *dptr);
+t_stat dcx_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *dcx_description (DEVICE *dptr);
 
 /* DCI data structures
 
@@ -632,7 +632,7 @@ dci_dib.lnt = newln * 010;                             /* upd IO page lnt */
 return auto_config (dci_dev.name, newln);              /* auto config */
 }
 
-t_stat dcx_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat dcx_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "DC11 Additional Terminal Interfaces (DCI/DCO)\n\n");
 fprintf (st, "For very early system programs, the PDP-11 simulator supports up to sixteen\n");
@@ -677,7 +677,7 @@ fprintf (st, "are lost when the simulator shuts down or DCI is detached.\n");
 return SCPE_OK;
 }
 
-char *dcx_description (DEVICE *dptr)
+const char *dcx_description (DEVICE *dptr)
 {
 return (dptr == &dci_dev) ? "DC11 asynchronous line interface - receiver" 
                           : "DC11 asynchronous line interface - transmitter";
diff --git a/PDP11/pdp11_dmc.c b/PDP11/pdp11_dmc.c
index 06d78cee..e0e01113 100644
--- a/PDP11/pdp11_dmc.c
+++ b/PDP11/pdp11_dmc.c
@@ -311,7 +311,7 @@ typedef struct queuehdr QH;
 
 typedef struct buffer_queue {
     QH hdr;                             /* Forward/Back Buffer pointers */
-    char * name;                        /* Queue name */
+    const char * name;                  /* Queue name */
     size_t size;                        /* Maximum number of entries (0 means no limit) */
     size_t count;                       /* Current Used Count */
     struct dmc_controller *controller;  /* back pointer to the containing controller */
@@ -929,10 +929,10 @@ t_stat dmc_showqueues (FILE* st, UNIT* uptr, int32 val, void* desc);
 t_stat dmc_setconnectpoll (UNIT* uptr, int32 val, char* cptr, void* desc);
 t_stat dmc_showconnectpoll (FILE* st, UNIT* uptr, int32 val, void* desc);
 t_stat dmc_showddcmp (FILE* st, UNIT* uptr, int32 val, void* desc);
-t_stat dmc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat dmc_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *dmc_description (DEVICE *dptr);
-char *dmp_description (DEVICE *dptr);
+t_stat dmc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat dmc_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *dmc_description (DEVICE *dptr);
+const char *dmp_description (DEVICE *dptr);
 int dmc_is_attached (UNIT* uptr);
 int dmc_is_dmc (CTLR *controller);
 int dmc_is_rqi_set (CTLR *controller);
@@ -949,7 +949,7 @@ void dmc_clr_modem_dtr (CTLR *controller);
 void dmc_process_command (CTLR *controller);
 t_bool dmc_buffer_fill_receive_buffers (CTLR *controller);
 void dmc_start_transfer_buffer (CTLR *controller);
-void dmc_buffer_queue_init (CTLR *controller, BUFFER_QUEUE *q, char *name, size_t size, BUFFER *buffers);
+void dmc_buffer_queue_init (CTLR *controller, BUFFER_QUEUE *q, const char *name, size_t size, BUFFER *buffers);
 void dmc_buffer_queue_init_all (CTLR *controller);
 BUFFER *dmc_buffer_queue_head (BUFFER_QUEUE *q);
 BUFFER *dmc_buffer_allocate (CTLR *controller);
@@ -1653,7 +1653,7 @@ fprintf(st, "   TimeRemaining: %d\n", controller->link.TimeRemaining);
 return SCPE_OK;
 }
 
-t_stat dmc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat dmc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char helpString[] =
  /* The '*'s in the next line represent the standard text width of a help line */
@@ -1850,7 +1850,7 @@ sprintf (connectpoll, "%d", DMC_CONNECT_POLL);
 return scp_help (st, dptr, uptr, flag, helpString, cptr, devname, devcount, connectpoll);
 }
 
-t_stat dmc_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat dmc_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 return dmc_help (st, dptr, uptr, flag, DMC_HLP_ATTACH);
 }
@@ -1918,11 +1918,11 @@ ans &= mask;
 return ans;
 }
 
-void dmc_dumpregsel0(CTLR *controller, int trace_level, char * prefix, uint16 data)
+void dmc_dumpregsel0(CTLR *controller, int trace_level, const char * prefix, uint16 data)
 {
-char *type_str = "";
+const char *type_str = "";
 uint16 type = dmc_bitfld(data, DMC_SEL0_V_ITYPE, DMC_SEL0_S_ITYPE);
-static char *dmc_types[] = {"XMT BA/CC", "CNTL IN", "HALT", "BASE IN", "RCV BA/CC", "?????",  "?????", "?????"};
+static const char *dmc_types[] = {"XMT BA/CC", "CNTL IN", "HALT", "BASE IN", "RCV BA/CC", "?????",  "?????", "?????"};
 
 if (dmc_is_dmc(controller)) {
     if (dmc_is_rqi_set(controller)) {
@@ -1965,11 +1965,11 @@ else {
     }
 }
 
-void dmc_dumpregsel2(CTLR *controller, int trace_level, char *prefix, uint16 data)
+void dmc_dumpregsel2(CTLR *controller, int trace_level, const char *prefix, uint16 data)
 {
-char *type_str = "";
+const char *type_str = "";
 uint16 type = dmc_bitfld(data, DMC_SEL2_V_CODE, DMC_SEL2_S_CODE);
-static char *dmc_types[] = {"XMT BA/CC OUT", "CNTL OUT", "?????", "?????", "RCV BA/CC OUT", "?????",  "?????", "?????"};
+static const char *dmc_types[] = {"XMT BA/CC OUT", "CNTL OUT", "?????", "?????", "RCV BA/CC OUT", "?????",  "?????", "?????"};
 
 type_str = dmc_types[type];
 
@@ -1989,7 +1989,7 @@ sim_debug(
     );
 }
 
-void dmc_dumpregsel4(CTLR *controller, int trace_level, char *prefix, uint16 data)
+void dmc_dumpregsel4(CTLR *controller, int trace_level, const char *prefix, uint16 data)
 {
 if (dmc_is_rdyi_set(controller)) {
     sim_debug(
@@ -2019,7 +2019,7 @@ else {
     }
 }
 
-void dmc_dumpregsel6(CTLR *controller, int trace_level, char *prefix, uint16 data)
+void dmc_dumpregsel6(CTLR *controller, int trace_level, const char *prefix, uint16 data)
 {
 if (dmc_is_rdyi_set(controller)) {
     sim_debug(
@@ -2043,7 +2043,7 @@ else {
     }
 }
 
-void dmc_dumpregsel10(CTLR *controller, int trace_level, char *prefix, uint16 data)
+void dmc_dumpregsel10(CTLR *controller, int trace_level, const char *prefix, uint16 data)
 {
 sim_debug(
     trace_level,
@@ -2090,7 +2090,7 @@ return ans;
 
 void dmc_setreg(CTLR *controller, int reg, uint16 data, int ctx)
 {
-char *trace = "Setting";
+const char *trace = "Setting";
 
 switch (dmc_getsel(reg)) {
     case 00:
@@ -2554,7 +2554,7 @@ if (active)
 return SCPE_OK;
 }
 
-void dmc_buffer_queue_init(CTLR *controller, BUFFER_QUEUE *q, char *name, size_t size, BUFFER *buffers)
+void dmc_buffer_queue_init(CTLR *controller, BUFFER_QUEUE *q, const char *name, size_t size, BUFFER *buffers)
 {
 q->name = name;
 initqueue (&q->hdr, q, size, buffers, sizeof(*buffers));
@@ -2642,7 +2642,7 @@ return ((q->hdr.next == &q->hdr) ? NULL : (BUFFER *)q->hdr.next);
 
 void dmc_queue_control_out(CTLR *controller, uint16 sel6)
 {
-CONTROL_OUT *control = calloc(1, sizeof(*control));
+CONTROL_OUT *control = (CONTROL_OUT *)calloc(1, sizeof(*control));
 CONTROL_OUT *last = NULL;
 
 control->sel6 = sel6;
@@ -2811,8 +2811,8 @@ else {  /* DMP */
 
         if (controller->transfer_type == DMP_C_TYPE_MODE) {
             uint16 mode = sel6 & DMP_TYPE_INPUT_MASK;
-            char * duplex = (mode & 1) ? "Full-Duplex" : "Half-Duplex";
-            char * config;
+            const char * duplex = (mode & 1) ? "Full-Duplex" : "Half-Duplex";
+            const char * config;
 
             if (mode & 4)
                 config = "Point-to-point";
@@ -3856,7 +3856,7 @@ uptr->filename = NULL;
 return r;
 }
 
-char *dmc_description (DEVICE *dptr)
+const char *dmc_description (DEVICE *dptr)
 {
 #if defined (VM_PDP10)
 return "DMR11 Synchronous network controller";
@@ -3865,7 +3865,7 @@ return "DMC11 Synchronous network controller";
 #endif
 }
 
-char *dmp_description (DEVICE *dptr)
+const char *dmp_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "DMP11 Synchronous network controller"
                 : "DMV11 Synchronous network controller";
diff --git a/PDP11/pdp11_dup.c b/PDP11/pdp11_dup.c
index 3a6b414b..c44731c2 100644
--- a/PDP11/pdp11_dup.c
+++ b/PDP11/pdp11_dup.c
@@ -123,9 +123,9 @@ static t_stat dup_set_W5 (UNIT* uptr, int32 val, char* cptr, void* desc);
 static t_stat dup_show_W5 (FILE* st, UNIT* uptr, int32 val, void* desc);
 static t_stat dup_set_W6 (UNIT* uptr, int32 val, char* cptr, void* desc);
 static t_stat dup_show_W6 (FILE* st, UNIT* uptr, int32 val, void* desc);
-static t_stat dup_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-static t_stat dup_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-static char *dup_description (DEVICE *dptr);
+static t_stat dup_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+static t_stat dup_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+static const char *dup_description (DEVICE *dptr);
 
 /* RXCSR - 16XXX0 - receiver control/status register */
 
@@ -472,9 +472,9 @@ DEVICE dpv_dev = {
 #define DUPDPTR ((UNIBUS) ? &dup_dev : &dpv_dev)
 
 /* Register names for Debug tracing */
-static char *dup_rd_regs[] =
+static const char *dup_rd_regs[] =
     {"RXCSR ", "RXDBUF", "TXCSR ", "TXDBUF" };
-static char *dup_wr_regs[] = 
+static const char *dup_wr_regs[] = 
     {"RXCSR ", "PARCSR", "TXCSR ", "TXDBUF"};
 
 
@@ -1466,7 +1466,7 @@ dptr->numunits = newln + 1;
 return dup_reset (dptr);                            /* setup lines and auto config */
 }
 
-static t_stat dup_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+static t_stat dup_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char helpString[] =
  /* The '*'s in the next line represent the standard text width of a help line */
@@ -1650,12 +1650,12 @@ sprintf (connectpoll, "%d", DUP_CONNECT_POLL);
 return scp_help (st, dptr, uptr, flag, helpString, cptr, busname, devcount, connectpoll);
 }
 
-static t_stat dup_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+static t_stat dup_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 return dup_help (st, dptr, uptr, flag, DUP_HLP_ATTACH);
 }
 
-static char *dup_description (DEVICE *dptr)
+static const char *dup_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "DUP11 bit synchronous interface" :
                   "DPV11 bit synchronous interface";
diff --git a/PDP11/pdp11_dz.c b/PDP11/pdp11_dz.c
index 6e7bb748..b07cf7c5 100644
--- a/PDP11/pdp11_dz.c
+++ b/PDP11/pdp11_dz.c
@@ -278,9 +278,9 @@ t_stat dz_setnl (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat dz_set_log (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat dz_set_nolog (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat dz_show_log (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat dz_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat dz_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *dz_description (DEVICE *dptr);
+t_stat dz_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat dz_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *dz_description (DEVICE *dptr);
 
 /* DZ data structures
 
@@ -360,9 +360,9 @@ DEVICE dz_dev = {
     };
 
 /* Register names for Debug tracing */
-static char *dz_rd_regs[] =
+static const char *dz_rd_regs[] =
     {"CSR ", "RBUF", "TCR ", "MSR " };
-static char *dz_wr_regs[] = 
+static const char *dz_wr_regs[] = 
     {"CSR ", "LPR ", "TCR ", "TDR "};
 
 /* IO dispatch routines, I/O addresses 177601x0 - 177601x7 */
@@ -742,7 +742,7 @@ int32 i, ndev;
 sim_debug(DBG_TRC, dptr, "dz_reset()\n");
 
 if (dz_ldsc == NULL)
-    dz_desc.ldsc = dz_ldsc = calloc (dz_desc.lines, sizeof(*dz_ldsc));
+    dz_desc.ldsc = dz_ldsc = (TMLN *)calloc (dz_desc.lines, sizeof(*dz_ldsc));
 for (i = 0; i < dz_desc.lines/DZ_LINES; i++)            /* init muxes */
     dz_clear (i, TRUE);
 dz_rxi = dz_txi = 0;                                    /* clr master int */
@@ -831,7 +831,7 @@ if (newln < dz_desc.lines) {
         }
     }
 dz_dib.lnt = (newln / DZ_LINES) * IOLN_DZ;              /* set length */
-dz_desc.ldsc = dz_ldsc = realloc(dz_ldsc, newln*sizeof(*dz_ldsc));
+dz_desc.ldsc = dz_ldsc = (TMLN *)realloc(dz_ldsc, newln*sizeof(*dz_ldsc));
 if (dz_desc.lines < newln)
     memset (dz_ldsc + dz_desc.lines, 0, sizeof(*dz_ldsc)*(newln-dz_desc.lines));
 dz_desc.lines = newln;
@@ -887,9 +887,9 @@ for (i = 0; i < dz_desc.lines; i++) {
 return SCPE_OK;
 }
 
-t_stat dz_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat dz_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
-char *devtype = (UNIBUS) ? "DZ11" : "DZV11";
+const char *devtype = (UNIBUS) ? "DZ11" : "DZV11";
 
 fprintf (st, "%s Terminal Multiplexer (DZ)\n\n", devtype);
 fprintf (st, "The %s is a %d line terminal multiplexor.  Up to %d %s's (%d lines) are\n", devtype, DZ_LINES, MAX_DZ_MUXES, devtype, DZ_LINES*MAX_DZ_MUXES);
@@ -928,9 +928,9 @@ dz_help_attach (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-t_stat dz_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat dz_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
-char *devtype = (UNIBUS) ? "DZ11" : "DZV11";
+const char *devtype = (UNIBUS) ? "DZ11" : "DZV11";
 
 tmxr_attach_help (st, dptr, uptr, flag, cptr);
 fprintf (st, "The terminal lines perform input and output through Telnet sessions connected\n");
@@ -946,7 +946,7 @@ fprintf (st, "status.\n\n");
 return SCPE_OK;
 }
 
-char *dz_description (DEVICE *dptr)
+const char *dz_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "DZ11 8-line terminal multiplexer" : "DZV11 4-line terminal multiplexer";
 }
diff --git a/PDP11/pdp11_hk.c b/PDP11/pdp11_hk.c
index 4ada5a28..6701432f 100644
--- a/PDP11/pdp11_hk.c
+++ b/PDP11/pdp11_hk.c
@@ -479,7 +479,7 @@ BITFIELD hk_mr3_bits[] = {
   ENDBITS
 };
 
-char *hk_regnames[] = {
+const char *hk_regnames[] = {
     "HKCS1",
     "HKWC",
     "HKBA",
@@ -554,7 +554,6 @@ int16 hk_dif[HK_NUMDR] = { 0 };                         /* cylinder diff */
 static const uint8 reg_in_drive[16] = {
  0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
 
-DEVICE hk_dev;
 t_stat hk_rd (int32 *data, int32 PA, int32 access);
 t_stat hk_wr (int32 data, int32 PA, int32 access);
 t_stat hk_svc (UNIT *uptr);
@@ -571,8 +570,8 @@ void hk_err (int32 cs1e, int32 cs2e, int32 drve, int32 drv);
 void hk_go (int32 drv);
 t_stat hk_set_size (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat hk_set_bad (UNIT *uptr, int32 val, char *cptr, void *desc);
-t_stat hk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *hk_description (DEVICE *dptr);
+t_stat hk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *hk_description (DEVICE *dptr);
 
 /* HK data structures
 
@@ -1631,7 +1630,7 @@ return SCPE_NOFNC;
 
 #endif
 
-t_stat hk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat hk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "RK611/RK06,RK07 Cartridge Disk (HK)\n\n");
 fprintf (st, "RK611  options include the ability to set units write enabled or write locked,\n");
@@ -1655,7 +1654,7 @@ fprintf (st, "    OS I/O error  x          report error and stop\n");
 return SCPE_OK;
 }
 
-char *hk_description (DEVICE *dptr)
+const char *hk_description (DEVICE *dptr)
 {
 return "RK611/RK06(7) cartridge disk controller";
 }
diff --git a/PDP11/pdp11_io_lib.c b/PDP11/pdp11_io_lib.c
index 665f23a9..74aac1c3 100644
--- a/PDP11/pdp11_io_lib.c
+++ b/PDP11/pdp11_io_lib.c
@@ -278,7 +278,7 @@ t_stat build_ubus_tab (DEVICE *dptr, DIB *dibp)
 int32 i, idx, vec, hivec, ilvl, ibit;
 DEVICE *cdptr;
 size_t j;
-char *cdname;
+const char *cdname;
 
 if ((dptr == NULL) || (dibp == NULL))                   /* validate args */
     return SCPE_IERR;
@@ -533,7 +533,7 @@ return SCPE_OK;
 
 
 typedef struct {
-    char        *dnam[AUTO_MAXC];
+    const char  *dnam[AUTO_MAXC];
     int32       numc;
     int32       numv;
     uint32      amod;
@@ -750,7 +750,7 @@ AUTO_CON auto_tab[] = {/*c  #v  am vm  fxa   fxv */
 #define DEV_NEXUS 0
 #endif
 #endif
-t_stat auto_config (char *name, int32 nctrl)
+t_stat auto_config (const char *name, int32 nctrl)
 {
 uint32 csr = IOPAGEBASE + AUTO_CSRBASE;
 uint32 vec = VEC_Q + AUTO_VECBASE;
diff --git a/PDP11/pdp11_io_lib.h b/PDP11/pdp11_io_lib.h
index 80533ea2..a5b38f7c 100644
--- a/PDP11/pdp11_io_lib.h
+++ b/PDP11/pdp11_io_lib.h
@@ -36,7 +36,7 @@ t_stat set_vec (UNIT *uptr, int32 arg, char *cptr, void *desc);
 t_stat show_vec (FILE *st, UNIT *uptr, int32 arg, void *desc);
 t_stat show_vec_mux (FILE *st, UNIT *uptr, int32 arg, void *desc);
 t_stat show_iospace (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat auto_config (char *name, int32 nctrl);
+t_stat auto_config (const char *name, int32 nctrl);
 t_stat pdp11_bad_block (UNIT *uptr, int32 sec, int32 wds);
 void init_ubus_tab (void);
 t_stat build_ubus_tab (DEVICE *dptr, DIB *dibp);
diff --git a/PDP11/pdp11_ke.c b/PDP11/pdp11_ke.c
index 656e52ba..3d55d900 100644
--- a/PDP11/pdp11_ke.c
+++ b/PDP11/pdp11_ke.c
@@ -65,13 +65,12 @@ uint32 ke_MQ = 0;
 uint32 ke_SC = 0;
 uint32 ke_SR = 0;
 
-DEVICE ke_dev;
 t_stat ke_rd (int32 *data, int32 PA, int32 access);
 t_stat ke_wr (int32 data, int32 PA, int32 access);
 t_stat ke_reset (DEVICE *dptr);
 uint32 ke_set_SR (void);
-t_stat ke_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *ke_description (DEVICE *dptr);
+t_stat ke_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *ke_description (DEVICE *dptr);
 
 #define IOLN_KE         020
 
@@ -353,7 +352,7 @@ ke_MQ = 0;
 return auto_config(0, 0);
 }
 
-t_stat ke_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat ke_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *const text =
 /*567901234567890123456789012345678901234567890123456789012345678901234567890*/
@@ -377,7 +376,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *ke_description (DEVICE *dptr)
+const char *ke_description (DEVICE *dptr)
 {
 return "KE11-A extended arithmetic element";
 }
diff --git a/PDP11/pdp11_kg.c b/PDP11/pdp11_kg.c
index 882addba..41f571d1 100644
--- a/PDP11/pdp11_kg.c
+++ b/PDP11/pdp11_kg.c
@@ -175,8 +175,8 @@ static t_stat kg_wr (int32, int32, int32);
 static t_stat kg_reset (DEVICE *);
 static void do_poly (int, t_bool);
 static t_stat set_units (UNIT *, int32, char *, void *);
-t_stat kg_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *kg_description (DEVICE *dptr);
+t_stat kg_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *kg_description (DEVICE *dptr);
 
 /* 16-bit rotate right */
 
@@ -463,7 +463,7 @@ static t_stat set_units (UNIT *u, int32 val, char *s, void *desc)
     return (SCPE_OK);
 }
 
-t_stat kg_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat kg_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *const text =
 /*567901234567890123456789012345678901234567890123456789012345678901234567890*/
@@ -488,7 +488,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *kg_description (DEVICE *dptr)
+const char *kg_description (DEVICE *dptr)
 {
 return "KG11-A Communications Arithmetic Option";
 }
diff --git a/PDP11/pdp11_kmc.c b/PDP11/pdp11_kmc.c
index 9ee2acda..40a132c6 100644
--- a/PDP11/pdp11_kmc.c
+++ b/PDP11/pdp11_kmc.c
@@ -494,8 +494,8 @@ static t_stat kmc_showLineSpeed (FILE *st, UNIT *txup, int32 val, void *desc);
 static t_stat kmc_showStatus (FILE *st, UNIT *up, int32 v, void *dp);
 
 static t_stat kmc_help (FILE *st, struct sim_device *dptr,
-                        struct sim_unit *uptr, int32 flag, char *cptr); 
-static char *kmc_description (DEVICE *dptr);
+                        struct sim_unit *uptr, int32 flag, const char *cptr); 
+static const char *kmc_description (DEVICE *dptr);
 
 /* Global data */
 
@@ -2942,7 +2942,7 @@ t_stat kmc_showStatus (FILE *st, UNIT *up, int32 v,  void *dp) {
  */
 
 static t_stat kmc_help (FILE *st, struct sim_device *dptr,
-                         struct sim_unit *uptr, int32 flag, char *cptr) {
+                         struct sim_unit *uptr, int32 flag, const char *cptr) {
     const char *const text =
 " The KMC11-A is a general purpose microprocessor that is used in\n"
 " several DEC products.  The KDP is an emulation of one of those\n"
@@ -3071,6 +3071,6 @@ static t_stat kmc_help (FILE *st, struct sim_device *dptr,
 /* Description of this device.
  * Conventionally last function in the file.
  */
-static char *kmc_description (DEVICE *dptr) {
+static const char *kmc_description (DEVICE *dptr) {
     return "KMC11-A Synchronous line controller supporting only COMM IOP/DUP microcode";
 }
diff --git a/PDP11/pdp11_lp.c b/PDP11/pdp11_lp.c
index 8ca26417..0a98c0cd 100644
--- a/PDP11/pdp11_lp.c
+++ b/PDP11/pdp11_lp.c
@@ -56,15 +56,14 @@ extern int32 int_req[IPL_HLVL];
 int32 lpt_csr = 0;                                      /* control/status */
 int32 lpt_stopioe = 0;                                  /* stop on error */
 
-DEVICE lpt_dev;
 t_stat lpt_rd (int32 *data, int32 PA, int32 access);
 t_stat lpt_wr (int32 data, int32 PA, int32 access);
 t_stat lpt_svc (UNIT *uptr);
 t_stat lpt_reset (DEVICE *dptr);
 t_stat lpt_attach (UNIT *uptr, char *ptr);
 t_stat lpt_detach (UNIT *uptr);
-t_stat lpt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *lpt_description (DEVICE *dptr);
+t_stat lpt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *lpt_description (DEVICE *dptr);
 
 /* LPT data structures
 
@@ -204,7 +203,7 @@ lpt_csr = lpt_csr | CSR_ERR;
 return detach_unit (uptr);
 }
 
-t_stat lpt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat lpt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Line Printer (LPT)\n\n");
 fprintf (st, "The line printer (LPT) writes data to a disk file.  The POS register specifies\n");
@@ -221,7 +220,7 @@ fprintf (st, "    OS I/O error  x          report error and stop\n");
 return SCPE_OK;
 }
 
-char *lpt_description (DEVICE *dptr)
+const char *lpt_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "LP11 line printer" :
                   "LPV11 line printer";
diff --git a/PDP11/pdp11_pclk.c b/PDP11/pdp11_pclk.c
index 0984b1d3..6d2821eb 100644
--- a/PDP11/pdp11_pclk.c
+++ b/PDP11/pdp11_pclk.c
@@ -136,7 +136,6 @@ uint32 pclk_ctr = 0;                                    /* counter */
 static uint32 rate[4] = { 100000, 10000, 60, 10 };      /* ticks per second */
 static uint32 xtim[4] = { 10, 100, 16667, 100000 };     /* nominal time delay */
 
-DEVICE pclk_dev;
 t_stat pclk_rd (int32 *data, int32 PA, int32 access);
 t_stat pclk_wr (int32 data, int32 PA, int32 access);
 t_stat pclk_svc (UNIT *uptr);
diff --git a/PDP11/pdp11_pt.c b/PDP11/pdp11_pt.c
index 27a21201..f5c27426 100644
--- a/PDP11/pdp11_pt.c
+++ b/PDP11/pdp11_pt.c
@@ -58,21 +58,20 @@ int32 ptr_stopioe = 0;                                  /* stop on error */
 int32 ptp_csr = 0;                                      /* control/status */
 int32 ptp_stopioe = 0;                                  /* stop on error */
 
-DEVICE ptr_dev, ptp_dev;
 t_stat ptr_rd (int32 *data, int32 PA, int32 access);
 t_stat ptr_wr (int32 data, int32 PA, int32 access);
 t_stat ptr_svc (UNIT *uptr);
 t_stat ptr_reset (DEVICE *dptr);
-t_stat ptr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *ptr_description (DEVICE *dptr);
+t_stat ptr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *ptr_description (DEVICE *dptr);
 t_stat ptr_attach (UNIT *uptr, char *ptr);
 t_stat ptr_detach (UNIT *uptr);
 t_stat ptp_rd (int32 *data, int32 PA, int32 access);
 t_stat ptp_wr (int32 data, int32 PA, int32 access);
 t_stat ptp_svc (UNIT *uptr);
 t_stat ptp_reset (DEVICE *dptr);
-t_stat ptp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *ptp_description (DEVICE *dptr);
+t_stat ptp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *ptp_description (DEVICE *dptr);
 t_stat ptp_attach (UNIT *uptr, char *ptr);
 t_stat ptp_detach (UNIT *uptr);
 
@@ -95,6 +94,7 @@ UNIT ptr_unit = {
            SERIAL_IN_WAIT
     };
 
+extern DEVICE ptr_dev;
 REG ptr_reg[] = {
     { GRDATAD (BUF,     ptr_unit.buf, DEV_RDX,  8, 0, "last data item processed") },
     { GRDATAD (CSR,          ptr_csr, DEV_RDX, 16, 0, "control/status register") },
@@ -380,7 +380,7 @@ ptp_csr = ptp_csr | CSR_ERR;
 return detach_unit (uptr);
 }
 
-t_stat ptr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat ptr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "PC11 Paper Tape Reader (PTR)\n\n");
 fprintf (st, "The paper tape reader (PTR) reads data from a disk file.  The POS register\n");
@@ -399,12 +399,12 @@ fprintf (st, "    OS I/O error  x          report error and stop\n");
 return SCPE_OK;
 }
 
-char *ptr_description (DEVICE *dptr)
+const char *ptr_description (DEVICE *dptr)
 {
 return "PC11 paper tape reader";
 }
 
-t_stat ptp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat ptp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "PC11 Paper Tape Punch (PTP)\n\n");
 fprintf (st, "The paper tape punch (PTP) writes data to a disk file.  The POS register\n");
@@ -421,7 +421,7 @@ fprintf (st, "    OS I/O error  x          report error and stop\n");
 return SCPE_OK;
 }
 
-char *ptp_description (DEVICE *dptr)
+const char *ptp_description (DEVICE *dptr)
 {
 return "PC11 paper tape punch";
 }
diff --git a/PDP11/pdp11_rc.c b/PDP11/pdp11_rc.c
index f90c2bf9..d2c15906 100644
--- a/PDP11/pdp11_rc.c
+++ b/PDP11/pdp11_rc.c
@@ -164,7 +164,6 @@ static uint32   rc_stopioe = 1;                         /* stop on error */
 
 /* forward references */
 
-DEVICE rc_dev;
 static t_stat rc_rd (int32 *, int32, int32);
 static t_stat rc_wr (int32, int32, int32);
 static t_stat rc_svc (UNIT *);
@@ -172,7 +171,7 @@ static t_stat rc_reset (DEVICE *);
 static t_stat rc_attach (UNIT *, char *);
 static t_stat rc_set_size (UNIT *, int32, char *, void *);
 static uint32 update_rccs (uint32, uint32);
-static char *rc_description (DEVICE *dptr);
+static const char *rc_description (DEVICE *dptr);
 
 /* RC11 data structures
 
@@ -246,7 +245,7 @@ DEVICE rc_dev = {
     NULL,                                               /* detach */
     &rc_dib,
     DEV_DISABLE | DEV_DIS | DEV_UBUS | DEV_DEBUG, 0,
-    NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, 
     &rc_description
 };
 
@@ -592,7 +591,7 @@ static t_stat rc_set_size (UNIT *uptr, int32 val, char *cptr, void *desc)
     return (SCPE_OK);
 }
 
-static char *rc_description (DEVICE *dptr)
+static const char *rc_description (DEVICE *dptr)
 {
     return "RC11/RS64 fixed head disk controller";
 }
diff --git a/PDP11/pdp11_rf.c b/PDP11/pdp11_rf.c
index 46a5f60b..54e68b1f 100644
--- a/PDP11/pdp11_rf.c
+++ b/PDP11/pdp11_rf.c
@@ -125,7 +125,6 @@ uint32 rf_time = 10;                                    /* inter-word time */
 uint32 rf_burst = 1;                                    /* burst mode flag */
 uint32 rf_stopioe = 1;                                  /* stop on error */
 
-DEVICE rf_dev;
 t_stat rf_rd (int32 *data, int32 PA, int32 access);
 t_stat rf_wr (int32 data, int32 PA, int32 access);
 int32 rf_inta (void);
@@ -135,8 +134,8 @@ t_stat rf_boot (int32 unitno, DEVICE *dptr);
 t_stat rf_attach (UNIT *uptr, char *cptr);
 t_stat rf_set_size (UNIT *uptr, int32 val, char *cptr, void *desc);
 uint32 update_rfcs (uint32 newcs, uint32 newdae);
-t_stat rf_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rf_description (DEVICE *dptr);
+t_stat rf_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rf_description (DEVICE *dptr);
 
 /* RF11 data structures
 
@@ -508,7 +507,7 @@ uptr->flags = uptr->flags & ~UNIT_AUTO;
 return SCPE_OK;
 }
 
-t_stat rf_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rf_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *text2, *text3;
 const char *const text =
@@ -567,7 +566,7 @@ fprintf (st, "%s", text3);
 return SCPE_OK;
 }
 
-char *rf_description (DEVICE *dptr)
+const char *rf_description (DEVICE *dptr)
 {
 return "RF11-A Fixed Head Disk controller";
 }
diff --git a/PDP11/pdp11_rh.c b/PDP11/pdp11_rh.c
index 2bc094bf..b0a3dd16 100644
--- a/PDP11/pdp11_rh.c
+++ b/PDP11/pdp11_rh.c
@@ -179,8 +179,8 @@ void mba_clr_int (uint32 mb);
 void mba_upd_cs1 (uint32 set, uint32 clr, uint32 mb);
 void mba_set_cs2 (uint32 flg, uint32 mb);
 int32 mba_map_pa (int32 pa, int32 *ofs);
-t_stat rh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rh_description (DEVICE *dptr);
+t_stat rh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rh_description (DEVICE *dptr);
 
 extern uint32 Map_Addr (uint32 ba);
 
@@ -921,7 +921,7 @@ if (dibp->ack[0])                                       /* set abort dispatch */
 return SCPE_OK;
 }
 
-t_stat rh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *const text =
 /*567901234567890123456789012345678901234567890123456789012345678901234567890*/
@@ -945,7 +945,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *rh_description (DEVICE *dptr)
+const char *rh_description (DEVICE *dptr)
 {
 if (dptr == &mba_dev[0])
     return "RH70/RH11 Massbus adapter (for RP)";
diff --git a/PDP11/pdp11_rk.c b/PDP11/pdp11_rk.c
index 704ef2c6..65a64293 100644
--- a/PDP11/pdp11_rk.c
+++ b/PDP11/pdp11_rk.c
@@ -282,7 +282,7 @@ int32 rk_stopioe = 1;                                   /* stop on error */
 int32 rk_swait = 10;                                    /* seek time */
 int32 rk_rwait = 10;                                    /* rotate time */
 
-char *rk_regnames[] = {
+const char *rk_regnames[] = {
     "RKDS",
     "RKER",
     "RKCS",
@@ -302,7 +302,6 @@ int32 *rk_regs[] = {
     &rkda,
     };
 
-DEVICE rk_dev;
 t_stat rk_rd (int32 *data, int32 PA, int32 access);
 t_stat rk_wr (int32 data, int32 PA, int32 access);
 int32 rk_inta (void);
@@ -312,8 +311,8 @@ void rk_go (void);
 void rk_set_done (int32 error);
 void rk_clr_done (void);
 t_stat rk_boot (int32 unitno, DEVICE *dptr);
-t_stat rk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rk_description (DEVICE *dptr);
+t_stat rk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rk_description (DEVICE *dptr);
 
 DEBTAB rk_deb[] = {
     { "OPS", RKDEB_OPS },
@@ -906,7 +905,7 @@ cpu_set_boot (BOOT_ENTRY);
 return SCPE_OK;
 }
 
-t_stat rk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *const text =
 /*567901234567890123456789012345678901234567890123456789012345678901234567890*/
@@ -954,7 +953,7 @@ fprintf (st, "    OS I/O error  x          report error and stop\n");
 return SCPE_OK;
 }
 
-char *rk_description (DEVICE *dptr)
+const char *rk_description (DEVICE *dptr)
 {
 return "RK11/RKV11 cartridge disk controller";
 }
diff --git a/PDP11/pdp11_rl.c b/PDP11/pdp11_rl.c
index 1662b021..b5f7e3af 100644
--- a/PDP11/pdp11_rl.c
+++ b/PDP11/pdp11_rl.c
@@ -240,7 +240,6 @@ int32 rl_rwait = 10;                                    /* rotate wait */
 int32 rl_stopioe = 1;                                   /* stop on error */
 
 /* forward references */
-DEVICE rl_dev;
 t_stat rl_rd (int32 *data, int32 PA, int32 access);
 t_stat rl_wr (int32 data, int32 PA, int32 access);
 t_stat rl_svc (UNIT *uptr);
@@ -261,8 +260,8 @@ t_stat rl_show_dstate (FILE *, UNIT *, int32, void *);
 t_stat rl_set_ctrl (UNIT *uptr, int32 val, char *cptr, void *desc);
 #endif
 t_stat rl_show_ctrl (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat rl_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rl_description (DEVICE *dptr);
+t_stat rl_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rl_description (DEVICE *dptr);
 
 /* RL11 data structures
 
@@ -1147,7 +1146,7 @@ t_stat rl_set_ctrl (UNIT *uptr, int32 val, char *cptr, void *desc)
 /* SHOW RL will display the controller type */
 t_stat rl_show_ctrl (FILE *st, UNIT *uptr, int32 val, void *desc)
 {
-    char    *s = "RLV12";
+    const char *s = "RLV12";
 
     if (UNIBUS)
         s = "RL11";
@@ -1231,7 +1230,7 @@ return SCPE_NOFNC;
 
 #endif
 
-t_stat rl_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rl_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "RL11/RL01/RL02 Cartridge Disk (RL)\n\n");
 fprintf (st, "RL11 options include the ability to set units write enabled or write locked,\n");
@@ -1254,7 +1253,7 @@ fprintf (st, "    OS I/O error  x          report error and stop\n");
 return SCPE_OK;
 }
 
-char *rl_description (DEVICE *dptr)
+const char *rl_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "RL11/RL01(2) cartridge disk controller" :
                   "RLV12/RL01(2) cartridge disk controller";
diff --git a/PDP11/pdp11_rp.c b/PDP11/pdp11_rp.c
index 8e65ee03..eb2ce78d 100644
--- a/PDP11/pdp11_rp.c
+++ b/PDP11/pdp11_rp.c
@@ -537,7 +537,7 @@ struct drvtyp {
     int32       size;                                   /* #blocks */
     int32       devtype;                                /* device type */
     int32       ctrl;                                   /* ctrl type */
-    char        *name;                                  /* device type name */
+    const char  *name;                                  /* device type name */
     };
 
 static struct drvtyp drv_tab[] = {
@@ -583,8 +583,8 @@ t_stat rp_go (int32 drv);
 t_stat rp_set_size (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat rp_set_bad (UNIT *uptr, int32 val, char *cptr, void *desc);
 int32 rp_abort (void);
-t_stat rp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rp_description (DEVICE *dptr);
+t_stat rp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rp_description (DEVICE *dptr);
 
 
 /* RP data structures
@@ -716,7 +716,7 @@ DEVICE rp_dev = {
     &rp_description
     };
 
-char *rp_regnam[] = 
+const char *rp_regnam[] = 
     {
     "RP_CS1",    /* 0 */
     "RP_DS",     /* 1 */
@@ -1189,13 +1189,13 @@ if (!uptr->io_complete) { /* Top End (I/O Initiation) Processing */
                 awc = (wc + (RP_NUMWD - 1)) & ~(RP_NUMWD - 1);
                 for (i = wc; i < awc; i++)              /* fill buf */
                     rpxb[drv][i] = 0;
-                sim_disk_data_trace (uptr, (void *)rpxb[drv], da/RP_NUMWD, awc, "sim_disk_wrsect-WR", DBG_DAT & dptr->dctrl, DBG_REQ);
-                sim_disk_wrsect_a (uptr, da/RP_NUMWD, (void *)rpxb[drv], NULL, awc/RP_NUMWD, rp_io_complete);
+                sim_disk_data_trace (uptr, (uint8 *)rpxb[drv], da/RP_NUMWD, awc, "sim_disk_wrsect-WR", DBG_DAT & dptr->dctrl, DBG_REQ);
+                sim_disk_wrsect_a (uptr, da/RP_NUMWD, (uint8 *)rpxb[drv], NULL, awc/RP_NUMWD, rp_io_complete);
                 return SCPE_OK;
                 }                                       /* end if wr */
             else {                                      /* read or wchk */
                 awc = (wc + (RP_NUMWD - 1)) & ~(RP_NUMWD - 1);
-                sim_disk_rdsect_a (uptr, da/RP_NUMWD, (void *)rpxb[drv], (t_seccnt*)&uptr->sectsread, awc/RP_NUMWD, rp_io_complete);
+                sim_disk_rdsect_a (uptr, da/RP_NUMWD, (uint8 *)rpxb[drv], (t_seccnt*)&uptr->sectsread, awc/RP_NUMWD, rp_io_complete);
                 return SCPE_OK;
                 }                                       /* end if read */
 
@@ -1493,7 +1493,7 @@ return SCPE_NOFNC;
 
 #endif
 
-t_stat rp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "RP04/05/06/07, RM02/03/05/80 Disk Pack Drives (RP)\n\n");
 fprintf (st, "The RP controller implements the Massbus family of large disk drives.  RP\n");
@@ -1518,7 +1518,7 @@ sim_disk_attach_help (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-char *rp_description (DEVICE *dptr)
+const char *rp_description (DEVICE *dptr)
 {
 return "RP04/05/06/07 RM02/03/05/80 Massbus disk controller";
 }
diff --git a/PDP11/pdp11_rq.c b/PDP11/pdp11_rq.c
index ecd27207..92f2aa70 100644
--- a/PDP11/pdp11_rq.c
+++ b/PDP11/pdp11_rq.c
@@ -695,7 +695,7 @@ struct drvtyp {
     uint16      mod;                                    /* MSCP model */
     int32       med;                                    /* MSCP media */
     int32       flgs;                                   /* flags */
-    char        *name;                                  /* name */
+    const char  *name;                                  /* name */
     };
 
 #define RQ_DRV(d) \
@@ -734,7 +734,7 @@ static struct drvtyp drv_tab[] = {
 struct ctlrtyp {
     uint32      uqpm;                                   /* port model */
     uint16      model;                                  /* controller model */
-    char        *name;                                  /* name */
+    const char  *name;                                  /* name */
     };
 
 #define RQ_CTLR(d) \
@@ -802,7 +802,7 @@ DEBTAB rq_debug[] = {
   {0}
 };
 
-static char *rq_cmdname[] = {
+static const char *rq_cmdname[] = {
     "",                                                 /*  0 */
     "ABO",                                              /*  1 b: abort */
     "GCS",                                              /*  2 b: get command status */
@@ -833,8 +833,6 @@ static char *rq_cmdname[] = {
     "AVA",                                              /* 64 b: unit now avail */
     };
 
-DEVICE rq_dev, rqb_dev, rqc_dev, rqd_dev;
-
 t_stat rq_rd (int32 *data, int32 PA, int32 access);
 t_stat rq_wr (int32 data, int32 PA, int32 access);
 t_stat rq_svc (UNIT *uptr);
@@ -852,8 +850,8 @@ t_stat rq_show_ctype (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat rq_show_wlk (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat rq_show_ctrl (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat rq_show_unitq (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat rq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rq_description (DEVICE *dptr);
+t_stat rq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rq_description (DEVICE *dptr);
 
 t_bool rq_step4 (MSC *cp);
 t_bool rq_mscp (MSC *cp, uint16 pkt, t_bool q);
@@ -2166,23 +2164,23 @@ if (!uptr->io_complete) { /* Top End (I/O Initiation) Processing */
     if (cmd == OP_ERS) {                                /* erase? */
         wwc = ((tbc + (RQ_NUMBY - 1)) & ~(RQ_NUMBY - 1)) >> 1;
         memset (uptr->rqxb, 0, wwc * sizeof(uint16));   /* clr buf */
-        sim_disk_data_trace(uptr, uptr->rqxb, bl, wwc << 1, "sim_disk_wrsect-ERS", DBG_DAT & rq_devmap[cp->cnum]->dctrl, DBG_REQ);
-        err = sim_disk_wrsect_a (uptr, bl, uptr->rqxb, NULL, (wwc << 1) / RQ_NUMBY, rq_io_complete);
+        sim_disk_data_trace(uptr, (uint8 *)uptr->rqxb, bl, wwc << 1, "sim_disk_wrsect-ERS", DBG_DAT & rq_devmap[cp->cnum]->dctrl, DBG_REQ);
+        err = sim_disk_wrsect_a (uptr, bl, (uint8 *)uptr->rqxb, NULL, (wwc << 1) / RQ_NUMBY, rq_io_complete);
         }
 
     else if (cmd == OP_WR) {                            /* write? */
-        t = rq_readw (ba, tbc, ma, uptr->rqxb);         /* fetch buffer */
+        t = rq_readw (ba, tbc, ma, (uint16 *)uptr->rqxb);/* fetch buffer */
         if ((abc = tbc - t)) {                          /* any xfer? */
             wwc = ((abc + (RQ_NUMBY - 1)) & ~(RQ_NUMBY - 1)) >> 1;
             for (i = (abc >> 1); i < wwc; i++)
                 ((uint16 *)(uptr->rqxb))[i] = 0;
-            sim_disk_data_trace(uptr, uptr->rqxb, bl, wwc << 1, "sim_disk_wrsect-WR", DBG_DAT & rq_devmap[cp->cnum]->dctrl, DBG_REQ);
-            err = sim_disk_wrsect_a (uptr, bl, uptr->rqxb, NULL, (wwc << 1) / RQ_NUMBY, rq_io_complete);
+            sim_disk_data_trace(uptr, (uint8 *)uptr->rqxb, bl, wwc << 1, "sim_disk_wrsect-WR", DBG_DAT & rq_devmap[cp->cnum]->dctrl, DBG_REQ);
+            err = sim_disk_wrsect_a (uptr, bl, (uint8 *)uptr->rqxb, NULL, (wwc << 1) / RQ_NUMBY, rq_io_complete);
             }
         }
 
     else {  /* OP_RD & OP_CMP */
-        err = sim_disk_rdsect_a (uptr, bl, uptr->rqxb, NULL, (tbc + RQ_NUMBY - 1) / RQ_NUMBY, rq_io_complete);
+        err = sim_disk_rdsect_a (uptr, bl, (uint8 *)uptr->rqxb, NULL, (tbc + RQ_NUMBY - 1) / RQ_NUMBY, rq_io_complete);
         }                                               /* end else read */
     return SCPE_OK;                                     /* done for now until callback */    
     }
@@ -2193,7 +2191,7 @@ else { /* Bottom End (After I/O processing) */
         }
 
     else if (cmd == OP_WR) {                            /* write? */
-        t = rq_readw (ba, tbc, ma, uptr->rqxb);         /* fetch buffer */
+        t = rq_readw (ba, tbc, ma, (uint16 *)uptr->rqxb);/* fetch buffer */
         abc = tbc - t;                                  /* any xfer? */
         if (t) {                                        /* nxm? */
             PUTP32 (pkt, RW_WBCL, bc - abc);            /* adj bc */
@@ -2205,9 +2203,9 @@ else { /* Bottom End (After I/O processing) */
         }
 
     else {
-        sim_disk_data_trace(uptr, uptr->rqxb, bl, tbc, "sim_disk_rdsect", DBG_DAT & rq_devmap[cp->cnum]->dctrl, DBG_REQ);
+        sim_disk_data_trace(uptr, (uint8 *)uptr->rqxb, bl, tbc, "sim_disk_rdsect", DBG_DAT & rq_devmap[cp->cnum]->dctrl, DBG_REQ);
         if ((cmd == OP_RD) && !err) {                   /* read? */
-            if ((t = rq_writew (ba, tbc, ma, uptr->rqxb))) {/* store, nxm? */
+            if ((t = rq_writew (ba, tbc, ma, (uint16 *)uptr->rqxb))) {/* store, nxm? */
                 PUTP32 (pkt, RW_WBCL, bc - (tbc - t));  /* adj bc */
                 PUTP32 (pkt, RW_WBAL, ba + (tbc - t));  /* adj ba */
                 if (rq_hbe (cp, uptr))                  /* post err log */
@@ -3147,7 +3145,7 @@ if (val & RQ_SH_UN) {
 return SCPE_OK;
 }
 
-t_stat rq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "UDA50 MSCP Disk Controller (%s)\n\n", dptr->name);
 fprintf (st, "The simulator implements four MSCP disk controllers, RQ, RQB, RQC, RQD.\n");
@@ -3184,7 +3182,7 @@ sim_disk_attach_help (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-char *rq_description (DEVICE *dptr)
+const char *rq_description (DEVICE *dptr)
 {
 static char buf[80];
 
diff --git a/PDP11/pdp11_rs.c b/PDP11/pdp11_rs.c
index 9d9d6ea8..431235b1 100644
--- a/PDP11/pdp11_rs.c
+++ b/PDP11/pdp11_rs.c
@@ -186,8 +186,8 @@ void rs_update_ds (uint16 flg, int32 drv);
 t_stat rs_go (int32 drv);
 t_stat rs_set_size (UNIT *uptr, int32 val, char *cptr, void *desc);
 int32 rs_abort (void);
-t_stat rs_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rs_description (DEVICE *dptr);
+t_stat rs_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rs_description (DEVICE *dptr);
 
 /* RS data structures
 
@@ -695,7 +695,7 @@ cpu_set_boot (BOOT_ENTRY);
 return SCPE_OK;
 }
 
-t_stat rs_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rs_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "RS03/RS04 Massbus disk controller (RS)\n\n");
 fprintf (st, "The RS controller implements the Massbus family fixed head disks.  RS\n");
@@ -715,7 +715,7 @@ fprintf (st, "errors cannot occur.\n");
 return SCPE_OK;
 }
 
-char *rs_description (DEVICE *dptr)
+const char *rs_description (DEVICE *dptr)
 {
 return "RS03/RS04 Massbus disk controller";
 }
diff --git a/PDP11/pdp11_rx.c b/PDP11/pdp11_rx.c
index 408ecff4..eee674bc 100644
--- a/PDP11/pdp11_rx.c
+++ b/PDP11/pdp11_rx.c
@@ -126,7 +126,6 @@ uint8 rx_buf[RX_NUMBY] = { 0 };                         /* sector buffer */
 int32 rx_bptr = 0;                                      /* buffer pointer */
 int32 rx_enb = 1;                                       /* device enable */
 
-DEVICE rx_dev;
 t_stat rx_rd (int32 *data, int32 PA, int32 access);
 t_stat rx_wr (int32 data, int32 PA, int32 access);
 t_stat rx_svc (UNIT *uptr);
diff --git a/PDP11/pdp11_ry.c b/PDP11/pdp11_ry.c
index 47a4b3e0..92472d8a 100644
--- a/PDP11/pdp11_ry.c
+++ b/PDP11/pdp11_ry.c
@@ -157,7 +157,6 @@ int32 ry_swait = 10;                                    /* seek, per track */
 int32 ry_xwait = 1;                                     /* tr set time */
 uint8 rx2xb[RY_NUMBY] = { 0 };                          /* sector buffer */
 
-DEVICE ry_dev;
 t_stat ry_rd (int32 *data, int32 PA, int32 access);
 t_stat ry_wr (int32 data, int32 PA, int32 access);
 t_stat ry_svc (UNIT *uptr);
@@ -166,8 +165,8 @@ t_stat ry_boot (int32 unitno, DEVICE *dptr);
 void ry_done (int32 esr_flags, uint8 new_ecode);
 t_stat ry_set_size (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat ry_attach (UNIT *uptr, char *cptr);
-t_stat ry_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *ry_description (DEVICE *dptr);
+t_stat ry_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *ry_description (DEVICE *dptr);
 
 
 /* RY11 data structures
@@ -714,7 +713,7 @@ return SCPE_NOFNC;
 
 #endif
 
-t_stat ry_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat ry_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "RX211/RX02 Floppy Disk\n\n");
 fprintf (st, "RX211 options include the ability to set units write enabled or write locked,\n");
@@ -736,7 +735,7 @@ fprintf (st, "errors cannot occur.\n");
 return SCPE_OK;
 }
 
-char *ry_description (DEVICE *dptr)
+const char *ry_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "RX211 floppy disk controller" : 
                   "RXV21 floppy disk controller";
diff --git a/PDP11/pdp11_ta.c b/PDP11/pdp11_ta.c
index bbc3e17c..fca9a736 100644
--- a/PDP11/pdp11_ta.c
+++ b/PDP11/pdp11_ta.c
@@ -125,7 +125,6 @@ static uint8 ta_fnc_tab[TACS_M_FNC + 1] = {
     OP_REV       , OP_FWD,        OP_FWD, 0
     };
 
-DEVICE ta_dev;
 t_stat ta_rd (int32 *data, int32 PA, int32 access);
 t_stat ta_wr (int32 data, int32 PA, int32 access);
 t_stat ta_svc (UNIT *uptr);
@@ -139,8 +138,8 @@ UNIT *ta_busy (void);
 void ta_set_tr (void);
 uint32 ta_updsta (UNIT *uptr);
 uint32 ta_crc (uint8 *buf, uint32 cnt);
-t_stat ta_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *ta_description (DEVICE *dptr);
+t_stat ta_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *ta_description (DEVICE *dptr);
 
 /* TA data structures
 
@@ -671,7 +670,7 @@ cpu_set_boot (BOOT_ENTRY);
 return SCPE_OK;
 }
 
-t_stat ta_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat ta_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *const text =
 /*567901234567890123456789012345678901234567890123456789012345678901234567890*/
@@ -698,7 +697,7 @@ sim_tape_attach_help (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-char *ta_description (DEVICE *dptr)
+const char *ta_description (DEVICE *dptr)
 {
 return "TA11/TA60 Cassette Tape";
 }
diff --git a/PDP11/pdp11_tc.c b/PDP11/pdp11_tc.c
index 1672c4c4..ebfdb425 100644
--- a/PDP11/pdp11_tc.c
+++ b/PDP11/pdp11_tc.c
@@ -289,7 +289,6 @@ int32 dt_substate = 0;
 int32 dt_logblk = 0;
 int32 dt_stopoffr = 0;
 
-DEVICE dt_dev;
 t_stat dt_rd (int32 *data, int32 PA, int32 access);
 t_stat dt_wr (int32 data, int32 PA, int32 access);
 t_stat dt_svc (UNIT *uptr);
@@ -309,8 +308,8 @@ void dt_stopunit (UNIT *uptr);
 int32 dt_comobv (int32 val);
 int32 dt_csum (UNIT *uptr, int32 blk);
 int32 dt_gethdr (UNIT *uptr, int32 blk, int32 relpos);
-t_stat dt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *dt_description (DEVICE *dptr);
+t_stat dt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *dt_description (DEVICE *dptr);
 
 /* DT data structures
 
@@ -1367,7 +1366,7 @@ uptr->capac = DT_CAPAC;                                 /* default size */
 return detach_unit (uptr);
 }
 
-t_stat dt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat dt_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *text2;
 const char *const text =
@@ -1515,7 +1514,7 @@ fprintf (st, "%s", text2);
 return SCPE_OK;
 }
 
-char *dt_description (DEVICE *dptr)
+const char *dt_description (DEVICE *dptr)
 {
 return "TC11/TU56 DECtape controller";
 }
diff --git a/PDP11/pdp11_tm.c b/PDP11/pdp11_tm.c
index df218c18..3201dee0 100644
--- a/PDP11/pdp11_tm.c
+++ b/PDP11/pdp11_tm.c
@@ -166,7 +166,6 @@ int32 tm_rdl = 0;                                       /* read lines */
 int32 tm_time = 10;                                     /* record latency */
 int32 tm_stopioe = 1;                                   /* stop on error */
 
-DEVICE tm_dev;
 t_stat tm_rd (int32 *data, int32 PA, int32 access);
 t_stat tm_wr (int32 data, int32 PA, int32 access);
 t_stat tm_svc (UNIT *uptr);
@@ -179,8 +178,8 @@ int32 tm_updcsta (UNIT *uptr);
 void tm_set_done (void);
 t_stat tm_map_err (UNIT *uptr, t_stat st);
 t_stat tm_vlock (UNIT *uptr, int32 val, char *cptr, void *desc);
-t_stat tm_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *tm_description (DEVICE *dptr);
+t_stat tm_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *tm_description (DEVICE *dptr);
 
 /* MT data structures
 
@@ -736,7 +735,7 @@ cpu_set_boot (BOOT_ENTRY);
 return SCPE_OK;
 } 
 
-t_stat tm_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tm_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char *text2;
 const char *const text =
@@ -789,7 +788,7 @@ sim_tape_attach_help (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-char *tm_description (DEVICE *dptr)
+const char *tm_description (DEVICE *dptr)
 {
 return "TM11 Magnet Tape controller";
 }
diff --git a/PDP11/pdp11_tq.c b/PDP11/pdp11_tq.c
index b7951e9e..0c083929 100644
--- a/PDP11/pdp11_tq.c
+++ b/PDP11/pdp11_tq.c
@@ -233,7 +233,7 @@ struct drvtyp {
     uint16      cver;
     uint16      fver;
     uint16      uver;
-    char        *name;
+    const char  *name;
     };
 
 static struct drvtyp drv_tab[] = {
@@ -309,7 +309,7 @@ static uint32 tq_cmf[64] = {
     0, 0, 0, 0, 0, 0, 0, 0
     };  
 
-static char *tq_cmdname[] = {
+static const char *tq_cmdname[] = {
     "",                                                 /*  0 */
     "ABO",                                              /*  1 b: abort */
     "GCS",                                              /*  2 b: get command status */
@@ -342,8 +342,6 @@ static char *tq_cmdname[] = {
 
 /* Forward references */
 
-DEVICE tq_dev;
-
 t_stat tq_rd (int32 *data, int32 PA, int32 access);
 t_stat tq_wr (int32 data, int32 PA, int32 access);
 int32 tq_inta (void);
@@ -358,8 +356,8 @@ t_stat tq_show_ctrl (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat tq_show_unitq (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat tq_set_type (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat tq_show_type (FILE *st, UNIT *uptr, int32 val, void *desc);
-static t_stat tq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *tq_description (DEVICE *dptr);
+static t_stat tq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *tq_description (DEVICE *dptr);
 
 t_bool tq_step4 (void);
 t_bool tq_mscp (uint16 pkt, t_bool q);
@@ -2392,9 +2390,9 @@ fprintf (st, "%s (%dMB)", drv_tab[tq_typ].name, (uint32) (drv_tab[tq_typ].cap >>
 return SCPE_OK;
 }
 
-static t_stat tq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+static t_stat tq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
-char *devtype = UNIBUS ? "TUK50" : "TQK50";
+const char *devtype = UNIBUS ? "TUK50" : "TQK50";
 
 fprintf (st, "%s (TQ)\n\n", tq_description (dptr));
 fprintf (st, "The TQ controller simulates the %s TMSCP disk controller.  TQ options\n", devtype);
@@ -2413,7 +2411,7 @@ sim_tape_attach_help (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-char *tq_description (DEVICE *dptr)
+const char *tq_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "TUK50 TMSCP magnetic tape controller" :
                   "TQK50 TMSCP magnetic tape controller";
diff --git a/PDP11/pdp11_ts.c b/PDP11/pdp11_ts.c
index 9b105cd6..1108863a 100644
--- a/PDP11/pdp11_ts.c
+++ b/PDP11/pdp11_ts.c
@@ -285,7 +285,6 @@ int32 ts_bcmd = 0;                                      /* boot cmd */
 int32 ts_time = 10;                                     /* record latency */
 static uint16 cpy_buf[MAX_PLNT];                        /* copy buffer */
 
-DEVICE ts_dev;
 t_stat ts_rd (int32 *data, int32 PA, int32 access);
 t_stat ts_wr (int32 data, int32 PA, int32 access);
 t_stat ts_svc (UNIT *uptr);
@@ -298,8 +297,8 @@ int32 ts_updxs0 (int32 t);
 void ts_cmpendcmd (int32 s0, int32 s1);
 void ts_endcmd (int32 ssf, int32 xs0f, int32 msg);
 int32 ts_map_status (t_stat st);
-t_stat ts_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *ts_description (DEVICE *dptr);
+t_stat ts_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *ts_description (DEVICE *dptr);
 
 /* TS data structures
 
@@ -1191,7 +1190,7 @@ return SCPE_NOFNC;
 }
 #endif
 
-t_stat ts_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat ts_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "TS11 Magnetic Tape (TS)\n\n");
 fprint_set_help (st, dptr);
@@ -1212,7 +1211,7 @@ sim_tape_attach_help (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-char *ts_description (DEVICE *dptr)
+const char *ts_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "TS11 magnetic tape controller" :
                   "TSV11/TSV05 magnetic tape controller ";
diff --git a/PDP11/pdp11_tu.c b/PDP11/pdp11_tu.c
index 1bdc8373..8b9352c9 100644
--- a/PDP11/pdp11_tu.c
+++ b/PDP11/pdp11_tu.c
@@ -233,7 +233,7 @@ static int32 fmt_test[16] = {                           /* fmt valid */
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0
     };
 static int32 dt_map[3] = { DT_TU16, DT_TU45, DT_TU77 };
-static char *tu_fname[CS1_N_FNC] = {
+static const char *tu_fname[CS1_N_FNC] = {
     "NOP", "UNLD", "2", "REW", "FCLR", "5", "6", "7",
     "RIP", "11", "ERASE", "WREOF", "SPCF", "SPCR", "16", "17",
     "20", "21", "22", "23", "WRCHKF", "25", "26", "WRCHKR",
@@ -249,8 +249,8 @@ t_stat tu_detach (UNIT *uptr);
 t_stat tu_boot (int32 unitno, DEVICE *dptr);
 t_stat tu_set_fmtr (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat tu_show_fmtr (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat tu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *tu_description (DEVICE *dptr);
+t_stat tu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *tu_description (DEVICE *dptr);
 t_stat tu_go (int32 drv);
 int32 tu_abort (void);
 void tu_set_er (int32 flg);
@@ -1065,7 +1065,7 @@ return SCPE_NOFNC;
 
 #endif
 
-t_stat tu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "TM02/TM03/TE16/TU45/TU77 Magnetic Tapes\n\n");
 fprintf (st, "The TU controller implements the Massbus family of 800/1600bpi magnetic tape\n");
@@ -1088,7 +1088,7 @@ fprintf (st, "    OS I/O error    parity error; if STOP_IOE, stop\n");
 return SCPE_OK;
 }
 
-char *tu_description (DEVICE *dptr)
+const char *tu_description (DEVICE *dptr)
 {
 return "TM03 tape formatter";
 }
diff --git a/PDP11/pdp11_vh.c b/PDP11/pdp11_vh.c
index 2f7e3c63..cf8a9d13 100644
--- a/PDP11/pdp11_vh.c
+++ b/PDP11/pdp11_vh.c
@@ -345,9 +345,9 @@ static t_stat vh_setnl (UNIT *uptr, int32 val, char *cptr, void *desc);
 static t_stat vh_set_log (UNIT *uptr, int32 val, char *cptr, void *desc);
 static t_stat vh_set_nolog (UNIT *uptr, int32 val, char *cptr, void *desc);
 static t_stat vh_show_log (FILE *st, UNIT *uptr, int32 val, void *desc);
-static t_stat vh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-static t_stat vh_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-static char *vh_description (DEVICE *dptr);
+static t_stat vh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+static t_stat vh_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+static const char *vh_description (DEVICE *dptr);
 
 /* SIMH I/O Structures */
 
@@ -464,13 +464,13 @@ DEVICE vh_dev = {
 };
 
 /* Register names for Debug tracing */
-static char *vh_rd_dhv_regs[] =
+static const char *vh_rd_dhv_regs[] =
     {"CSR   ", "RBUF  ", "LPR   ", "STAT  ", "LNCTRL", "TBFAD1", "TBFAD2", "TBFCNT" };
-static char *vh_wr_dhv_regs[] =
+static const char *vh_wr_dhv_regs[] =
     {"CSR   ", "TXCHAR", "LPR   ", "STAT  ", "LNCTRL", "TBFAD1", "TBFAD2", "TBFCNT" };
-static char *vh_rd_dhu_regs[] =
+static const char *vh_rd_dhu_regs[] =
     {"CSR   ", "RBUF  ", "LPR   ", "FIFOSZ", "LNCTRL", "TBFAD1", "TBFAD2", "TBFCNT" };
-static char *vh_wr_dhu_regs[] =
+static const char *vh_wr_dhu_regs[] =
     {"CSR   ", "RXTIMR", "LPR   ", "FIFODT", "LNCTRL", "TBFAD1", "TBFAD2", "TBFCNT" };
 
 /* Interrupt routines */
@@ -1557,9 +1557,9 @@ for (i = 0; i < vh_desc.lines; i++) {
 return SCPE_OK;
 }
 
-static t_stat vh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+static t_stat vh_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
-char *devtype = (UNIBUS) ? "DH11" : "DHQ11";
+const char *devtype = (UNIBUS) ? "DH11" : "DHQ11";
 
 fprintf (st, "%s Terminal Multiplexer (%s)\n\n", devtype, dptr->name);
 fprintf (st, "The %s is an %d-line terminal multiplexer for %s systems.  Up to %d %s's\n", devtype, VH_LINES, (UNIBUS) ? "Unibus" : "Qbus", VH_MUXES, devtype);
@@ -1612,15 +1612,15 @@ vh_help_attach (st, dptr, uptr, flag, cptr);
 return SCPE_OK;
 }
 
-static t_stat vh_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+static t_stat vh_help_attach (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
-char *devtype = (UNIBUS) ? "DH11" : "DHQ11";
+const char *devtype = (UNIBUS) ? "DH11" : "DHQ11";
 
 fprintf (st, "%s %s Terminal Multiplexer Attach Help\n\n", devtype, dptr->name);
 return tmxr_attach_help (st, dptr, uptr, 1, cptr);
 }
 
-static char *vh_description (DEVICE *dptr)
+static const char *vh_description (DEVICE *dptr)
 {
 return (UNIBUS) ? "DH11 16-line Terminal Multiplexer" : "DHQ11 8-line Terminal Multiplexer";
 }
diff --git a/PDP11/pdp11_xq.c b/PDP11/pdp11_xq.c
index 6c013aa6..91525afa 100644
--- a/PDP11/pdp11_xq.c
+++ b/PDP11/pdp11_xq.c
@@ -302,8 +302,8 @@ int32 xq_int (void);
 void xq_csr_set_clr(CTLR* xq, uint16 set_bits, uint16 clear_bits);
 void xq_show_debug_bdl(CTLR* xq, uint32 bdl_ba);
 t_stat xq_boot (int32 unitno, DEVICE *dptr);
-t_stat xq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *xq_description (DEVICE *dptr);
+t_stat xq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *xq_description (DEVICE *dptr);
 
 struct xq_device    xqa = {
   xqa_read_callback,                        /* read callback routine */
@@ -709,7 +709,7 @@ t_stat xq_set_stats (UNIT* uptr, int32 val, char* cptr, void* desc)
 
 t_stat xq_show_stats (FILE* st, UNIT* uptr, int32 val, void* desc)
 {
-  char* fmt = "  %-15s%d\n";
+  const char* fmt = "  %-15s%d\n";
   CTLR* xq = xq_unit2ctlr(uptr);
 
   fprintf(st, "XQ Ethernet statistics:\n");
@@ -1499,7 +1499,7 @@ t_stat xq_process_xbdl(CTLR* xq)
 
     /* add to transmit buffer, making sure it's not too big */
     if ((xq->var->write_buffer.len + b_length) > sizeof(xq->var->write_buffer.msg)) {
-      xq->var->write_buffer.oversize = realloc (xq->var->write_buffer.oversize, xq->var->write_buffer.len + b_length);
+      xq->var->write_buffer.oversize = (uint8*)realloc (xq->var->write_buffer.oversize, xq->var->write_buffer.len + b_length);
       if (xq->var->write_buffer.len <= sizeof(xq->var->write_buffer.msg))
         memcpy (xq->var->write_buffer.oversize, xq->var->write_buffer.msg, xq->var->write_buffer.len);
       }
@@ -1865,7 +1865,7 @@ t_stat xq_process_turbo_xbdl(CTLR* xq)
 
     /* add to transmit buffer, accomodating it if it is too big */
     if ((xq->var->write_buffer.len + b_length) > sizeof(xq->var->write_buffer.msg)) {
-      xq->var->write_buffer.oversize = realloc (xq->var->write_buffer.oversize, xq->var->write_buffer.len + b_length);
+      xq->var->write_buffer.oversize = (uint8*)realloc (xq->var->write_buffer.oversize, xq->var->write_buffer.len + b_length);
       if (xq->var->write_buffer.len <= sizeof(xq->var->write_buffer.msg))
         memcpy (xq->var->write_buffer.oversize, xq->var->write_buffer.msg, xq->var->write_buffer.len);
       }
@@ -3074,7 +3074,7 @@ return SCPE_NOFNC;
 #endif
 }
 
-t_stat xq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat xq_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 const char helpString[] =
  /* The '*'s in the next line represent the standard text width of a help line */
@@ -3311,7 +3311,7 @@ const char helpString[] =
 return scp_help (st, dptr, uptr, flag, helpString, cptr);
 }
 
-char *xq_description (DEVICE *dptr)
+const char *xq_description (DEVICE *dptr)
 {
 return (dptr == &xq_dev) ? "DELQA/DEQNA Ethernet controller"
                          : "Second DELQA/DEQNA Ethernet controller";
diff --git a/PDP11/pdp11_xu.c b/PDP11/pdp11_xu.c
index 3193adfc..867dc328 100644
--- a/PDP11/pdp11_xu.c
+++ b/PDP11/pdp11_xu.c
@@ -130,8 +130,8 @@ void xu_process_receive(CTLR* xu);
 void xu_dump_rxring(CTLR* xu);
 void xu_dump_txring(CTLR* xu);
 t_stat xu_show_filters (FILE* st, UNIT* uptr, int32 val, void* desc);
-t_stat xu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *xu_description (DEVICE *dptr);
+t_stat xu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *xu_description (DEVICE *dptr);
 
 #define IOLN_XU        010
 
@@ -395,7 +395,7 @@ t_stat xu_set_stats (UNIT* uptr, int32 val, char* cptr, void* desc)
 
 t_stat xu_show_stats (FILE* st, UNIT* uptr, int32 val, void* desc)
 {
-  char* fmt = "  %-26s%d\n";
+  const char* fmt = "  %-26s%d\n";
   CTLR* xu = xu_unit2ctlr(uptr);
   struct xu_stats* stats = &xu->var->stats;
 
@@ -873,7 +873,7 @@ int32 xu_command(CTLR* xu)
   uint16* mac_w = (uint16*) xu->var->mac;
   static const ETH_MAC zeros = {0,0,0,0,0,0};
   static const ETH_MAC mcast_load_server = {0xAB, 0x00, 0x00, 0x01, 0x00, 0x00};
-  static char* command[] = {
+  static const char* command[] = {
       "NO-OP",
       "Start Microaddress",
       "Read Default Physical Address",
@@ -1499,10 +1499,9 @@ void xu_process_transmit(CTLR* xu)
 
 void xu_port_command (CTLR* xu)
 {
-  char* msg;
   int command = xu->var->pcsr0 & PCSR0_PCMD;
   int state = xu->var->pcsr1 & PCSR1_STATE;
-  static char* commands[] = {
+  static const char* commands[] = {
       "NO-OP",
       "GET PCBB",
       "GET CMD",
@@ -1589,8 +1588,7 @@ void xu_port_command (CTLR* xu)
 
     case CMD_BOOT:      /* BOOT */
       /* not implemented */
-      msg = "%s: BOOT command not implemented!\n";
-      sim_printf (msg, xu->dev->name);
+      sim_printf ("%s: BOOT command not implemented!\n", xu->dev->name);
 
       xu->var->pcsr0 |= PCSR0_PCEI;
       break;
@@ -1883,7 +1881,7 @@ void xu_dump_txring (CTLR* xu)
   }
 }
 
-t_stat xu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat xu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "DELUA/DEUNA Unibus Ethernet Controllers (XU, XUB)\n\n");
 fprintf (st, "The simulator implements two DELUA/DEUNA Unibus Ethernet controllers (XU, XUB).\n");
@@ -1906,7 +1904,7 @@ fprintf (st, "card, and \"Feel the Power!\" :-)\n");
 return SCPE_OK;
 }
 
-char *xu_description (DEVICE *dptr)
+const char *xu_description (DEVICE *dptr)
 {
 return "DEUNA/DELUA Ethernet controller";
 }
diff --git a/VAX/vax610_stddev.c b/VAX/vax610_stddev.c
index d5b2b720..2680f602 100644
--- a/VAX/vax610_stddev.c
+++ b/VAX/vax610_stddev.c
@@ -88,11 +88,11 @@ t_stat clk_svc (UNIT *uptr);
 t_stat tti_reset (DEVICE *dptr);
 t_stat tto_reset (DEVICE *dptr);
 t_stat clk_reset (DEVICE *dptr);
-char *tti_description (DEVICE *dptr);
-char *tto_description (DEVICE *dptr);
-char *clk_description (DEVICE *dptr);
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+const char *tti_description (DEVICE *dptr);
+const char *tto_description (DEVICE *dptr);
+const char *clk_description (DEVICE *dptr);
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 void txdb_func (int32 data);
 
 extern int32 sysd_hlt_enb (void);
@@ -368,7 +368,7 @@ sim_activate_abs (&tti_unit, KBD_WAIT (tti_unit.wait, tmr_poll));
 return SCPE_OK;
 }
 
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Input (TTI)\n\n");
 fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
@@ -378,7 +378,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tti_description (DEVICE *dptr)
+const char *tti_description (DEVICE *dptr)
 {
 return "console terminal input";
 }
@@ -417,7 +417,7 @@ sim_cancel (&tto_unit);                                 /* deactivate unit */
 return SCPE_OK;
 }
 
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Output (TTO)\n\n");
 fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
@@ -427,7 +427,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tto_description (DEVICE *dptr)
+const char *tto_description (DEVICE *dptr)
 {
 return "console terminal output";
 }
@@ -468,7 +468,7 @@ tmxr_poll = t * TMXR_MULT;                              /* set mux poll */
 return SCPE_OK;
 }
 
-char *clk_description (DEVICE *dptr)
+const char *clk_description (DEVICE *dptr)
 {
 return "100hz clock tick";
 }
diff --git a/VAX/vax610_sysdev.c b/VAX/vax610_sysdev.c
index a9072c05..01296a8e 100644
--- a/VAX/vax610_sysdev.c
+++ b/VAX/vax610_sysdev.c
@@ -567,7 +567,7 @@ fprintf (st, (sys_model ? "VAXstation I" : "MicroVAX I"));
 return SCPE_OK;
 }
 
-t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Initial memory size is 4MB.\n\n");
 fprintf (st, "The simulator is booted with the BOOT command:\n\n");
diff --git a/VAX/vax630_io.c b/VAX/vax630_io.c
index 28394264..2f6a1a39 100644
--- a/VAX/vax630_io.c
+++ b/VAX/vax630_io.c
@@ -90,8 +90,8 @@ t_stat set_autocon (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat show_autocon (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat show_iospace (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat qba_show_virt (FILE *of, UNIT *uptr, int32 val, void *desc);
-t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *qba_description (DEVICE *dptr);
+t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *qba_description (DEVICE *dptr);
 
 /* Qbus adapter data structures
 
@@ -746,7 +746,7 @@ fprintf (of, "Invalid argument\n");
 return SCPE_OK;
 }
 
-t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Qbus Adapter (QBA)\n\n");
 fprintf (st, "The Qbus adapter (QBA) simulates the CQBIC Qbus adapter chip.\n");
@@ -760,7 +760,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *qba_description (DEVICE *dptr)
+const char *qba_description (DEVICE *dptr)
 {
 return "Qbus adapter";
 }
diff --git a/VAX/vax630_stddev.c b/VAX/vax630_stddev.c
index 29480123..09ae4b4b 100644
--- a/VAX/vax630_stddev.c
+++ b/VAX/vax630_stddev.c
@@ -65,11 +65,11 @@ t_stat clk_svc (UNIT *uptr);
 t_stat tti_reset (DEVICE *dptr);
 t_stat tto_reset (DEVICE *dptr);
 t_stat clk_reset (DEVICE *dptr);
-char *tti_description (DEVICE *dptr);
-char *tto_description (DEVICE *dptr);
-char *clk_description (DEVICE *dptr);
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+const char *tti_description (DEVICE *dptr);
+const char *tto_description (DEVICE *dptr);
+const char *clk_description (DEVICE *dptr);
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 
 extern int32 sysd_hlt_enb (void);
 
@@ -303,7 +303,7 @@ sim_activate_abs (&tti_unit, KBD_WAIT (tti_unit.wait, tmr_poll));
 return SCPE_OK;
 }
 
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Input (TTI)\n\n");
 fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
@@ -318,7 +318,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tti_description (DEVICE *dptr)
+const char *tti_description (DEVICE *dptr)
 {
 return "console terminal input";
 }
@@ -357,7 +357,7 @@ sim_cancel (&tto_unit);                                 /* deactivate unit */
 return SCPE_OK;
 }
 
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Output (TTO)\n\n");
 fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
@@ -367,7 +367,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tto_description (DEVICE *dptr)
+const char *tto_description (DEVICE *dptr)
 {
 return "console terminal output";
 }
@@ -409,7 +409,7 @@ tmxr_poll = t * TMXR_MULT;                              /* set mux poll */
 return SCPE_OK;
 }
 
-char *clk_description (DEVICE *dptr)
+const char *clk_description (DEVICE *dptr)
 {
 return "100hz clock tick";
 }
diff --git a/VAX/vax630_sysdev.c b/VAX/vax630_sysdev.c
index faca7c67..e991ac30 100644
--- a/VAX/vax630_sysdev.c
+++ b/VAX/vax630_sysdev.c
@@ -157,18 +157,18 @@ t_stat rom_dep (t_value val, t_addr exta, UNIT *uptr, int32 sw);
 t_stat rom_reset (DEVICE *dptr);
 t_stat rom_set_diag (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat rom_show_diag (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rom_description (DEVICE *dptr);
+t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rom_description (DEVICE *dptr);
 t_stat nvr_ex (t_value *vptr, t_addr exta, UNIT *uptr, int32 sw);
 t_stat nvr_dep (t_value val, t_addr exta, UNIT *uptr, int32 sw);
 t_stat nvr_reset (DEVICE *dptr);
-t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat nvr_attach (UNIT *uptr, char *cptr);
 t_stat nvr_detach (UNIT *uptr);
-char *nvr_description (DEVICE *dptr);
+const char *nvr_description (DEVICE *dptr);
 t_stat sysd_reset (DEVICE *dptr);
-t_stat sysd_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *sysd_description (DEVICE *dptr);
+t_stat sysd_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *sysd_description (DEVICE *dptr);
 
 int32 rom_rd (int32 pa);
 int32 nvr_rd (int32 pa);
@@ -416,7 +416,7 @@ if (rom == NULL)
 return SCPE_OK;
 }
 
-t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Read-only memory (ROM)\n\n");
 fprintf (st, "The boot ROM consists of a single unit, simulating the 64KB boot ROM.  It has\n");
@@ -440,7 +440,7 @@ fprintf (st, "    SET CPU DIAG=FULL       Run full diagnostics\n\n");
 return SCPE_OK;
 }
 
-char *rom_description (DEVICE *dptr)
+const char *rom_description (DEVICE *dptr)
 {
 return "read-only memory";
 }
@@ -530,7 +530,7 @@ if (nvr == NULL)
 return SCPE_OK;
 }
 
-t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Non-volatile Memory (NVR)\n\n");
 fprintf (st, "The NVR simulates %d bytes of battery-backed up memory.\n", NVRSIZE);
@@ -585,7 +585,7 @@ if ((uptr->flags & UNIT_ATT) == 0) {
 return r;
 }
 
-char *nvr_description (DEVICE *dptr)
+const char *nvr_description (DEVICE *dptr)
 {
 return "non-volatile memory";
 }
@@ -1035,7 +1035,7 @@ sim_vm_cmd = vax630_cmd;
 return SCPE_OK;
 }
 
-char *sysd_description (DEVICE *dptr)
+const char *sysd_description (DEVICE *dptr)
 {
 return "system devices";
 }
@@ -1090,7 +1090,7 @@ fprintf (st, (sys_model ? "VAXstation II" : "MicroVAX II"));
 return SCPE_OK;
 }
 
-t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Initial memory size is 16MB.\n\n");
 fprintf (st, "The CPU supports the BOOT command and is the only VAX device to do so.  Note\n");
diff --git a/VAX/vax730_stddev.c b/VAX/vax730_stddev.c
index c92ed500..a8ee3a87 100644
--- a/VAX/vax730_stddev.c
+++ b/VAX/vax730_stddev.c
@@ -215,14 +215,14 @@ t_stat tmr_svc (UNIT *uptr);
 t_stat tti_reset (DEVICE *dptr);
 t_stat tto_reset (DEVICE *dptr);
 t_stat clk_reset (DEVICE *dptr);
-char *tti_description (DEVICE *dptr);
-char *tto_description (DEVICE *dptr);
-char *clk_description (DEVICE *dptr);
-char *tmr_description (DEVICE *dptr);
-char *td_description (DEVICE *dptr);
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+const char *tti_description (DEVICE *dptr);
+const char *tto_description (DEVICE *dptr);
+const char *clk_description (DEVICE *dptr);
+const char *tmr_description (DEVICE *dptr);
+const char *td_description (DEVICE *dptr);
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat clk_attach (UNIT *uptr, char *cptr);
 t_stat clk_detach (UNIT *uptr);
 t_stat tmr_reset (DEVICE *dptr);
@@ -697,7 +697,7 @@ sim_activate_abs (&tti_unit, KBD_WAIT (tti_unit.wait, tmr_poll));
 return SCPE_OK;
 }
 
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Input (TTI)\n\n");
 fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
@@ -707,7 +707,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tti_description (DEVICE *dptr)
+const char *tti_description (DEVICE *dptr)
 {
 return "console terminal input";
 }
@@ -745,7 +745,7 @@ sim_cancel (&tto_unit);                                 /* deactivate unit */
 return SCPE_OK;
 }
 
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Output (TTO)\n\n");
 fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
@@ -755,7 +755,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tto_description (DEVICE *dptr)
+const char *tto_description (DEVICE *dptr)
 {
 return "console terminal output";
 }
@@ -922,7 +922,7 @@ if (clk_unit.filebuf == NULL) {                         /* make sure the TODR is
 return SCPE_OK;
 }
 
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Real-Time Clock (%s)\n\n", dptr->name);
 fprintf (st, "The real-time clock autocalibrates; the clock interval is adjusted up or down\n");
@@ -953,7 +953,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *clk_description (DEVICE *dptr)
+const char *clk_description (DEVICE *dptr)
 {
 return "time of year clock";
 }
@@ -1000,7 +1000,7 @@ todr_resync ();                                         /* resync TODR */
 return SCPE_OK;
 }
 
-char *tmr_description (DEVICE *dptr)
+const char *tmr_description (DEVICE *dptr)
 {
 return "interval timer";
 }
@@ -1284,7 +1284,7 @@ sim_cancel (&td_dev.units[1]);
 return SCPE_OK;
 }
 
-char *td_description (DEVICE *dptr)
+const char *td_description (DEVICE *dptr)
 {
 return "Console TU58 cartridge";
 }
diff --git a/VAX/vax730_sys.c b/VAX/vax730_sys.c
index 17b465a1..038e41e2 100644
--- a/VAX/vax730_sys.c
+++ b/VAX/vax730_sys.c
@@ -672,7 +672,7 @@ fprintf (st, "VAX 11/730");
 return SCPE_OK;
 }
 
-t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Initial memory size is 2MB.\n\n");
 fprintf (st, "The simulator is booted with the BOOT command:\n\n");
diff --git a/VAX/vax750_cmi.c b/VAX/vax750_cmi.c
index c96ee652..6f0ea88a 100644
--- a/VAX/vax750_cmi.c
+++ b/VAX/vax750_cmi.c
@@ -763,7 +763,7 @@ fprintf (st, "VAX 11/750");
 return SCPE_OK;
 }
 
-t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Initial memory size is 2MB.\n\n");
 fprintf (st, "The simulator is booted with the BOOT command:\n\n");
diff --git a/VAX/vax750_stddev.c b/VAX/vax750_stddev.c
index a28c4a78..27b49ae2 100644
--- a/VAX/vax750_stddev.c
+++ b/VAX/vax750_stddev.c
@@ -213,12 +213,12 @@ t_stat tmr_svc (UNIT *uptr);
 t_stat tti_reset (DEVICE *dptr);
 t_stat tto_reset (DEVICE *dptr);
 t_stat clk_reset (DEVICE *dptr);
-char *tti_description (DEVICE *dptr);
-char *tto_description (DEVICE *dptr);
-char *clk_description (DEVICE *dptr);
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+const char *tti_description (DEVICE *dptr);
+const char *tto_description (DEVICE *dptr);
+const char *clk_description (DEVICE *dptr);
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat clk_attach (UNIT *uptr, char *cptr);
 t_stat clk_detach (UNIT *uptr);
 t_stat tmr_reset (DEVICE *dptr);
@@ -693,7 +693,7 @@ csi_int = 0;
 return SCPE_OK;
 }
 
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Input (TTI)\n\n");
 fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
@@ -703,7 +703,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tti_description (DEVICE *dptr)
+const char *tti_description (DEVICE *dptr)
 {
 return "console terminal input";
 }
@@ -742,7 +742,7 @@ sim_cancel (&tto_unit);                                 /* deactivate unit */
 return SCPE_OK;
 }
 
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Output (TTO)\n\n");
 fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
@@ -752,7 +752,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tto_description (DEVICE *dptr)
+const char *tto_description (DEVICE *dptr)
 {
 return "console terminal output";
 }
@@ -919,7 +919,7 @@ if (clk_unit.filebuf == NULL) {                         /* make sure the TODR is
 return SCPE_OK;
 }
 
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Real-Time Clock (%s)\n\n", dptr->name);
 fprintf (st, "The real-time clock autocalibrates; the clock interval is adjusted up or down\n");
@@ -950,7 +950,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *clk_description (DEVICE *dptr)
+const char *clk_description (DEVICE *dptr)
 {
 return "time of year clock";
 }
diff --git a/VAX/vax780_sbi.c b/VAX/vax780_sbi.c
index a8a99085..41a31dfc 100644
--- a/VAX/vax780_sbi.c
+++ b/VAX/vax780_sbi.c
@@ -848,7 +848,7 @@ fprintf (st, "VAX 11/%s", (sys_model ? "785" : "780"));
 return SCPE_OK;
 }
 
-t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Initial memory size is 8MB.\n\n");
 fprintf (st, "The simulator is booted with the BOOT command:\n\n");
diff --git a/VAX/vax780_stddev.c b/VAX/vax780_stddev.c
index d19eeff0..ba062149 100644
--- a/VAX/vax780_stddev.c
+++ b/VAX/vax780_stddev.c
@@ -229,14 +229,14 @@ t_stat tmr_svc (UNIT *uptr);
 t_stat tti_reset (DEVICE *dptr);
 t_stat tto_reset (DEVICE *dptr);
 t_stat clk_reset (DEVICE *dptr);
-char *tti_description (DEVICE *dptr);
-char *tto_description (DEVICE *dptr);
-char *clk_description (DEVICE *dptr);
-char *tmr_description (DEVICE *dptr);
-char *fl_description (DEVICE *dptr);
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+const char *tti_description (DEVICE *dptr);
+const char *tto_description (DEVICE *dptr);
+const char *clk_description (DEVICE *dptr);
+const char *tmr_description (DEVICE *dptr);
+const char *fl_description (DEVICE *dptr);
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat clk_attach (UNIT *uptr, char *cptr);
 t_stat clk_detach (UNIT *uptr);
 t_stat tmr_reset (DEVICE *dptr);
@@ -510,7 +510,7 @@ sim_activate (&tti_unit, KBD_WAIT (tti_unit.wait, tmr_poll));
 return SCPE_OK;
 }
 
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Input (TTI)\n\n");
 fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
@@ -520,7 +520,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tti_description (DEVICE *dptr)
+const char *tti_description (DEVICE *dptr)
 {
 return "console terminal input";
 }
@@ -559,7 +559,7 @@ sim_cancel (&tto_unit);                                 /* deactivate unit */
 return SCPE_OK;
 }
 
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Output (TTO)\n\n");
 fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
@@ -569,7 +569,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tto_description (DEVICE *dptr)
+const char *tto_description (DEVICE *dptr)
 {
 return "console terminal output";
 }
@@ -736,7 +736,7 @@ if (clk_unit.filebuf == NULL) {                         /* make sure the TODR is
 return SCPE_OK;
 }
 
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Real-Time Clock (%s)\n\n", dptr->name);
 fprintf (st, "The real-time clock autocalibrates; the clock interval is adjusted up or down\n");
@@ -767,7 +767,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *clk_description (DEVICE *dptr)
+const char *clk_description (DEVICE *dptr)
 {
 return "time of year clock";
 }
@@ -815,7 +815,7 @@ todr_resync ();                                         /* resync TODR */
 return SCPE_OK;
 }
 
-char *tmr_description (DEVICE *dptr)
+const char *tmr_description (DEVICE *dptr)
 {
 return "interval timer";
 }
@@ -1167,7 +1167,7 @@ comm_region[COMM_GH] = 1;
 return SCPE_OK;
 }
 
-char *fl_description (DEVICE *dptr)
+const char *fl_description (DEVICE *dptr)
 {
 return "console floppy";
 }
diff --git a/VAX/vax780_uba.c b/VAX/vax780_uba.c
index dbbe8797..3dd369bb 100644
--- a/VAX/vax780_uba.c
+++ b/VAX/vax780_uba.c
@@ -184,8 +184,8 @@ extern uint32 nexus_req[NEXUS_HLVL];
 
 t_stat uba_svc (UNIT *uptr);
 t_stat uba_reset (DEVICE *dptr);
-t_stat uba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *uba_description (DEVICE *dptr);
+t_stat uba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *uba_description (DEVICE *dptr);
 t_stat uba_ex (t_value *vptr, t_addr exta, UNIT *uptr, int32 sw);
 t_stat uba_dep (t_value val, t_addr exta, UNIT *uptr, int32 sw);
 t_stat uba_rdreg (int32 *val, int32 pa, int32 mode);
@@ -935,7 +935,7 @@ uba_cnf = UBACNF_UBIC;
 return SCPE_OK;
 }
 
-t_stat uba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat uba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Unibus Adapter (UBA)\n\n");
 fprintf (st, "The Unibus adapter (UBA) simulates the DW780.\n");
@@ -949,7 +949,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *uba_description (DEVICE *dptr)
+const char *uba_description (DEVICE *dptr)
 {
 return "Unibus adapter";
 }
diff --git a/VAX/vax7x0_mba.c b/VAX/vax7x0_mba.c
index f52d11b1..760cade0 100644
--- a/VAX/vax7x0_mba.c
+++ b/VAX/vax7x0_mba.c
@@ -255,8 +255,8 @@ extern uint32 nexus_req[NEXUS_HLVL];
 extern UNIT cpu_unit;
 
 t_stat mba_reset (DEVICE *dptr);
-t_stat mba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *mba_description (DEVICE *dptr);
+t_stat mba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *mba_description (DEVICE *dptr);
 t_stat mba_rdreg (int32 *val, int32 pa, int32 mode);
 t_stat mba_wrreg (int32 val, int32 pa, int32 lnt);
 t_bool mba_map_addr (uint32 va, uint32 *ma, uint32 mb);
@@ -857,7 +857,7 @@ if (mbabort[mb])                                        /* reset device */
 return SCPE_OK;
 }
 
-t_stat mba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat mba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Massbus Adapters (MBA0, MBA1)\n\n");
 fprintf (st, "The Massbus adapters (MBA0, MBA1) simulate RH780's.  MBA0 is assigned to the\n");
@@ -868,7 +868,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *mba_description (DEVICE *dptr)
+const char *mba_description (DEVICE *dptr)
 {
 static char buf[64];
 
diff --git a/VAX/vax860_abus.c b/VAX/vax860_abus.c
index c359014f..d340645c 100644
--- a/VAX/vax860_abus.c
+++ b/VAX/vax860_abus.c
@@ -855,7 +855,7 @@ fprintf (st, "VAX %s", (sys_model ? "8650" : "8600"));
 return SCPE_OK;
 }
 
-t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Initial memory size is 32MB.\n\n");
 fprintf (st, "The simulator is booted with the BOOT command:\n\n");
diff --git a/VAX/vax860_stddev.c b/VAX/vax860_stddev.c
index 410ba1bd..037bcae0 100644
--- a/VAX/vax860_stddev.c
+++ b/VAX/vax860_stddev.c
@@ -245,14 +245,14 @@ t_stat rlcs_svc (UNIT *uptr);
 t_stat tti_reset (DEVICE *dptr);
 t_stat tto_reset (DEVICE *dptr);
 t_stat clk_reset (DEVICE *dptr);
-char *tti_description (DEVICE *dptr);
-char *tto_description (DEVICE *dptr);
-char *clk_description (DEVICE *dptr);
-char *tmr_description (DEVICE *dptr);
-char *rlcs_description (DEVICE *dptr);
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+const char *tti_description (DEVICE *dptr);
+const char *tto_description (DEVICE *dptr);
+const char *clk_description (DEVICE *dptr);
+const char *tmr_description (DEVICE *dptr);
+const char *rlcs_description (DEVICE *dptr);
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat clk_attach (UNIT *uptr, char *cptr);
 t_stat clk_detach (UNIT *uptr);
 t_stat tmr_reset (DEVICE *dptr);
@@ -631,7 +631,7 @@ sim_activate_abs (&tti_unit[ID_CT], KBD_WAIT (tti_unit[ID_CT].wait, tmr_poll));
 return SCPE_OK;
 }
 
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Input (TTI)\n\n");
 fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
@@ -641,7 +641,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tti_description (DEVICE *dptr)
+const char *tti_description (DEVICE *dptr)
 {
 return "console terminal input";
 }
@@ -693,7 +693,7 @@ sim_cancel (&tto_unit[ID_LC]);
 return SCPE_OK;
 }
 
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Output (TTO)\n\n");
 fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
@@ -703,7 +703,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tto_description (DEVICE *dptr)
+const char *tto_description (DEVICE *dptr)
 {
 return "console terminal output";
 }
@@ -870,7 +870,7 @@ if (clk_unit.filebuf == NULL) {                         /* make sure the TODR is
 return SCPE_OK;
 }
 
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Real-Time Clock (%s)\n\n", dptr->name);
 fprintf (st, "The real-time clock autocalibrates; the clock interval is adjusted up or down\n");
@@ -901,7 +901,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *clk_description (DEVICE *dptr)
+const char *clk_description (DEVICE *dptr)
 {
 return "time of year clock";
 }
@@ -948,7 +948,7 @@ todr_resync ();                                         /* resync TODR */
 return SCPE_OK;
 }
 
-char *tmr_description (DEVICE *dptr)
+const char *tmr_description (DEVICE *dptr)
 {
 return "interval timer";
 }
@@ -1230,7 +1230,7 @@ sim_cancel (&rlcs_unit);                                /* deactivate unit */
 return SCPE_OK;
 }
 
-char *rlcs_description (DEVICE *dptr)
+const char *rlcs_description (DEVICE *dptr)
 {
 return "Console RL02 disk";
 }
diff --git a/VAX/vax_cpu.c b/VAX/vax_cpu.c
index 92c20a7b..18be9f8e 100644
--- a/VAX/vax_cpu.c
+++ b/VAX/vax_cpu.c
@@ -395,7 +395,7 @@ t_stat cpu_show_hist (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat cpu_show_virt (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat cpu_set_idle (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat cpu_show_idle (FILE *st, UNIT *uptr, int32 val, void *desc);
-char *cpu_description (DEVICE *dptr);
+const char *cpu_description (DEVICE *dptr);
 int32 cpu_get_vsw (int32 sw);
 static SIM_INLINE int32 get_istr (int32 lnt, int32 acc);
 int32 ReadOcta (int32 va, int32 *opnd, int32 j, int32 acc);
@@ -534,7 +534,7 @@ fprintf (st, "model=");
 return cpu_print_model (st);
 }
 
-char *cpu_description (DEVICE *dptr)
+const char *cpu_description (DEVICE *dptr)
 {
 static char buf[80];
 uint32 min_mem = 4096, max_mem = 0;
@@ -3523,7 +3523,7 @@ return more;
 }
 
 struct os_idle {
-    char        *name;
+    const char        *name;
     uint32      mask;
     };
 
@@ -3598,7 +3598,7 @@ if (r != SCPE_OK) {
 return SCPE_OK;
 }
 
-t_stat cpu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "The ");cpu_print_model (st);fprintf (st, " CPU help\n\n");
 fprintf (st, "CPU options include the size of main memory.\n\n");
diff --git a/VAX/vax_defs.h b/VAX/vax_defs.h
index cf1ff84d..8e6a6577 100644
--- a/VAX/vax_defs.h
+++ b/VAX/vax_defs.h
@@ -758,7 +758,7 @@ extern t_stat cpu_load_bootcode (const char *filename, const unsigned char *buil
 extern t_stat cpu_print_model (FILE *st);
 extern t_stat cpu_show_model (FILE *st, UNIT *uptr, int32 val, void *desc);
 extern t_stat cpu_set_model (UNIT *uptr, int32 val, char *cptr, void *desc);
-extern t_stat cpu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-extern t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+extern t_stat cpu_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+extern t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 
 #endif                                                  /* _VAX_DEFS_H */
diff --git a/VAX/vax_io.c b/VAX/vax_io.c
index e361b304..fb96970d 100644
--- a/VAX/vax_io.c
+++ b/VAX/vax_io.c
@@ -136,8 +136,8 @@ t_stat set_autocon (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat show_autocon (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat show_iospace (FILE *st, UNIT *uptr, int32 val, void *desc);
 t_stat qba_show_virt (FILE *of, UNIT *uptr, int32 val, void *desc);
-t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *qba_description (DEVICE *dptr);
+t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *qba_description (DEVICE *dptr);
 
 /* Qbus adapter data structures
 
@@ -924,7 +924,7 @@ fprintf (of, "Invalid argument\n");
 return SCPE_OK;
 }
 
-t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat qba_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Qbus Adapter (QBA)\n\n");
 fprintf (st, "The Qbus adapter (QBA) simulates the CQBIC Qbus adapter chip.\n");
@@ -938,7 +938,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *qba_description (DEVICE *dptr)
+const char *qba_description (DEVICE *dptr)
 {
 return "Qbus adapter";
 }
diff --git a/VAX/vax_lk.c b/VAX/vax_lk.c
index 3b66a815..5378de32 100644
--- a/VAX/vax_lk.c
+++ b/VAX/vax_lk.c
@@ -170,7 +170,6 @@ uint8 lk_rbuf[10];                                      /* receive buffer */
 int32 lk_rbuf_p = 0;                                    /* receive buffer ptr */
 int32 lk_mode[16];                                      /* mode of each key group */
 
-DEVICE lk_dev;
 t_stat lk_wr (uint8 c);
 t_stat lk_rd (uint8 *c);
 t_stat lk_reset (DEVICE *dptr);
@@ -830,5 +829,5 @@ switch (mode) {
 }
 
 #else /* defined(VAX_620) */
-static char *dummy_declaration = "Something to compile";
+static const char *dummy_declaration = "Something to compile";
 #endif /* !defined(VAX_620) */
diff --git a/VAX/vax_stddev.c b/VAX/vax_stddev.c
index 1eb5cbc1..c59a87fb 100644
--- a/VAX/vax_stddev.c
+++ b/VAX/vax_stddev.c
@@ -120,12 +120,12 @@ t_stat clk_reset (DEVICE *dptr);
 t_stat clk_attach (UNIT *uptr, char *cptr);
 t_stat clk_detach (UNIT *uptr);
 t_stat todr_resync (void);
-char *tti_description (DEVICE *dptr);
-char *tto_description (DEVICE *dptr);
-char *clk_description (DEVICE *dptr);
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+const char *tti_description (DEVICE *dptr);
+const char *tto_description (DEVICE *dptr);
+const char *clk_description (DEVICE *dptr);
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 
 extern int32 sysd_hlt_enb (void);
 extern int32 fault_PC;
@@ -366,7 +366,7 @@ sim_activate (&tti_unit, KBD_WAIT (tti_unit.wait, tmr_poll));
 return SCPE_OK;
 }
 
-t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Input (TTI)\n\n");
 fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
@@ -381,7 +381,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tti_description (DEVICE *dptr)
+const char *tti_description (DEVICE *dptr)
 {
 return "console terminal input";
 }
@@ -420,7 +420,7 @@ sim_cancel (&tto_unit);                                 /* deactivate unit */
 return SCPE_OK;
 }
 
-t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Console Terminal Output (TTO)\n\n");
 fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
@@ -430,7 +430,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *tto_description (DEVICE *dptr)
+const char *tto_description (DEVICE *dptr)
 {
 return "console terminal output";
 }
@@ -559,7 +559,7 @@ if (clk_unit.filebuf == NULL) {                         /* make sure the TODR is
 return SCPE_OK;
 }
 
-t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Real-Time Clock (%s)\n\n", dptr->name);
 fprintf (st, "The real-time clock autocalibrates; the clock interval is adjusted up or down\n");
@@ -590,7 +590,7 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *clk_description (DEVICE *dptr)
+const char *clk_description (DEVICE *dptr)
 {
 return "time of year clock";
 }
diff --git a/VAX/vax_sysdev.c b/VAX/vax_sysdev.c
index b900d48e..a70ace85 100644
--- a/VAX/vax_sysdev.c
+++ b/VAX/vax_sysdev.c
@@ -238,24 +238,24 @@ static uint32 rom_delay = 0;
 t_stat rom_ex (t_value *vptr, t_addr exta, UNIT *uptr, int32 sw);
 t_stat rom_dep (t_value val, t_addr exta, UNIT *uptr, int32 sw);
 t_stat rom_reset (DEVICE *dptr);
-t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *rom_description (DEVICE *dptr);
+t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *rom_description (DEVICE *dptr);
 t_stat nvr_ex (t_value *vptr, t_addr exta, UNIT *uptr, int32 sw);
 t_stat nvr_dep (t_value val, t_addr exta, UNIT *uptr, int32 sw);
 t_stat nvr_reset (DEVICE *dptr);
 t_stat nvr_attach (UNIT *uptr, char *cptr);
 t_stat nvr_detach (UNIT *uptr);
-t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *nvr_description (DEVICE *dptr);
+t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *nvr_description (DEVICE *dptr);
 t_stat csi_reset (DEVICE *dptr);
-char *csi_description (DEVICE *dptr);
+const char *csi_description (DEVICE *dptr);
 t_stat cso_reset (DEVICE *dptr);
 t_stat cso_svc (UNIT *uptr);
-char *cso_description (DEVICE *dptr);
+const char *cso_description (DEVICE *dptr);
 t_stat tmr_svc (UNIT *uptr);
 t_stat sysd_reset (DEVICE *dptr);
-t_stat sysd_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *sysd_description (DEVICE *dptr);
+t_stat sysd_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *sysd_description (DEVICE *dptr);
 
 int32 rom_rd (int32 pa);
 int32 nvr_rd (int32 pa);
@@ -610,7 +610,7 @@ if (rom == NULL)
 return SCPE_OK;
 }
 
-t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat rom_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Read-only memory (ROM)\n\n");
 fprintf (st, "The boot ROM consists of a single unit, simulating the 128KB boot ROM.  It\n");
@@ -629,7 +629,7 @@ fprint_set_help (st, dptr);
 return SCPE_OK;
 }
 
-char *rom_description (DEVICE *dptr)
+const char *rom_description (DEVICE *dptr)
 {
 return "read-only memory";
 }
@@ -727,7 +727,7 @@ if ((uptr->flags & UNIT_ATT) == 0)
 return r;
 }
 
-t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat nvr_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Non-volatile Memory (NVR)\n\n");
 fprintf (st, "The NVR consists of a single unit, simulating 1KB of battery-backed up memory\n");
@@ -740,7 +740,7 @@ fprintf (st, "Successfully loading an NVR image clears the SSC battery-low indic
 return SCPE_OK;
 }
 
-char *nvr_description (DEVICE *dptr)
+const char *nvr_description (DEVICE *dptr)
 {
 return "non-volatile memory";
 }
@@ -777,7 +777,7 @@ CLR_INT (CSI);
 return SCPE_OK;
 }
 
-char *csi_description (DEVICE *dptr)
+const char *csi_description (DEVICE *dptr)
 {
 return "console storage input";
 }
@@ -833,7 +833,7 @@ sim_cancel (&cso_unit);                                 /* deactivate unit */
 return SCPE_OK;
 }
 
-char *cso_description (DEVICE *dptr)
+const char *cso_description (DEVICE *dptr)
 {
 return "console storage output";
 }
@@ -1788,7 +1788,7 @@ ssc_otp = 0;
 return SCPE_OK;
 }
 
-t_stat sysd_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat sysd_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "System Devices (SYSD)\n\n");
 fprintf (st, "The system devices are the system-specific facilities implemented in the CVAX\n");
@@ -1808,7 +1808,7 @@ fprintf (st, "setting the flag.  The default value is set.\n");
 return SCPE_OK;
 }
 
-char *sysd_description (DEVICE *dptr)
+const char *sysd_description (DEVICE *dptr)
 {
 return "system devices";
 }
@@ -1857,7 +1857,7 @@ fprintf (st, "%s 3900 (KA655)", (sys_model ? "MicroVAX" : "VAXServer"));
 return SCPE_OK;
 }
 
-t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat cpu_model_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Notes on memory size:\n\n");
 fprintf (st, "- The real KA655 CPU only supported 16MB to 64MB of memory.  The simulator\n");
diff --git a/VAX/vax_vc.c b/VAX/vax_vc.c
index c3503d6b..56464bc0 100644
--- a/VAX/vax_vc.c
+++ b/VAX/vax_vc.c
@@ -231,7 +231,6 @@ uint32 *vc_buf = NULL;                                  /* Video memory */
 uint32 *vc_lines = NULL;                                /* Video Display Lines */
 uint8 vc_cur[256];                                      /* Cursor image */
 
-DEVICE vc_dev;
 t_stat vc_rd (int32 *data, int32 PA, int32 access);
 t_stat vc_wr (int32 data, int32 PA, int32 access);
 t_stat vc_svc (UNIT *uptr);
@@ -244,8 +243,8 @@ void vc_setint (int32 src);
 int32 vc_inta (void);
 void vc_clrint (int32 src);
 void vc_uart_int (uint32 set);
-t_stat vc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *vc_description (DEVICE *dptr);
+t_stat vc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *vc_description (DEVICE *dptr);
 
 
 /* QVSS data structures
@@ -355,7 +354,7 @@ UART2681 vc_uart = {
     { { &lk_wr, &lk_rd }, { &vs_wr, &vs_rd } }
     };
 
-char *vc_regnames[] = {
+const char *vc_regnames[] = {
     "CSR",          /* +0 */
     "CUR-X",        /* +2 */
     "MPOS",         /* +4 */
@@ -391,7 +390,7 @@ char *vc_regnames[] = {
     "",             /* +62 spare */
 };
 
-char *vc_crtc_regnames[] = {
+const char *vc_crtc_regnames[] = {
     "HTOT",         /* Horizontal Total The total number of character times in a line, minus 1 */
     "HDSP",         /* Horizontal Displayed The total number of displayed characters in a line. */
     "HPOS",         /* HSYNC Position Defines the number of character times until HSYNC (horizontal sync). */
@@ -1081,7 +1080,7 @@ else
 return SCPE_OK;
 }
 
-t_stat vc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat vc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "VCB01 Monochrome Video Subsystem (%s)\n\n", dptr->name);
 fprintf (st, "Use the Control-Right-Shift key combination to regain focus from the simulated\n");
@@ -1092,11 +1091,11 @@ fprint_reg_help (st, dptr);
 return SCPE_OK;
 }
 
-char *vc_description (DEVICE *dptr)
+const char *vc_description (DEVICE *dptr)
 {
 return "VCB01 Monochrome Graphics Adapter";
 }
 
 #else /* defined(VAX_620) */
-static char *dummy_declaration = "Something to compile";
+static const char *dummy_declaration = "Something to compile";
 #endif /* !defined(VAX_620) */
diff --git a/VAX/vax_vs.c b/VAX/vax_vs.c
index 417d4962..61ed2642 100644
--- a/VAX/vax_vs.c
+++ b/VAX/vax_vs.c
@@ -72,7 +72,6 @@ t_bool vs_m = 0;                                        /* Middle button state *
 t_bool vs_r = 0;                                        /* Right button state */
 uint8 vs_buf[10];
 
-DEVICE vs_dev;
 t_stat vs_wr (uint8 c);
 t_stat vs_rd (uint8 *c);
 t_stat vs_reset (DEVICE *dptr);
@@ -241,5 +240,5 @@ if (vs_state == VSXXX_IDLE) {
 }
 
 #else /* defined(VAX_620) */
-static char *dummy_declaration = "Something to compile";
+static const char *dummy_declaration = "Something to compile";
 #endif /* !defined(VAX_620) */
diff --git a/VAX/vax_watch.c b/VAX/vax_watch.c
index 6e1bc99c..994026a2 100644
--- a/VAX/vax_watch.c
+++ b/VAX/vax_watch.c
@@ -109,8 +109,8 @@ int32 wtc_mode = WTC_MODE_VMS;
 
 t_stat wtc_set (UNIT *uptr, int32 val, char *cptr, void *desc);
 t_stat wtc_show (FILE *st, UNIT *uptr, int32 val, void *desc);
-t_stat wtc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
-char *wtc_description (DEVICE *dptr);
+t_stat wtc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
+const char *wtc_description (DEVICE *dptr);
 t_stat wtc_reset (DEVICE *dptr);
 void wtc_set_valid (void);
 void wtc_set_invalid (void);
@@ -301,7 +301,7 @@ void wtc_set_invalid (void)
 wtc_csrd &= ~WTC_CSRD_VRT;
 }
 
-t_stat wtc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat wtc_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "Watch Chip (WTC)\n\n");
 fprintf (st, "The WTC simulates the MC146818 watch chip.  It recognizes the following options:\n\n");
@@ -314,7 +314,7 @@ fprintf (st, "verify that the time reported is valid.  The default mode is VMS.\
 return SCPE_OK;
 }
 
-char *wtc_description (DEVICE *dptr)
+const char *wtc_description (DEVICE *dptr)
 {
 return "watch chip";
 }
diff --git a/scp.c b/scp.c
index e69f627e..8c98b4af 100644
--- a/scp.c
+++ b/scp.c
@@ -453,7 +453,7 @@ void int_handler (int signal);
 t_stat set_prompt (int32 flag, char *cptr);
 t_stat sim_set_asynch (int32 flag, char *cptr);
 t_stat sim_set_environment (int32 flag, char *cptr);
-static char *get_dbg_verb (uint32 dbits, DEVICE* dptr);
+static const char *get_dbg_verb (uint32 dbits, DEVICE* dptr);
 
 /* Global data */
 
@@ -533,8 +533,8 @@ const char save_vercur[] = "V3.5";
 const char save_ver32[] = "V3.2";
 const char save_ver30[] = "V3.0";
 const struct scp_error {
-    char *code;
-    char *message;
+    const char *code;
+    const char *message;
     } scp_errors[1+SCPE_MAX_ERR-SCPE_BASE] =
         {{"NXM",     "Address space exceeded"},
          {"UNATT",   "Unit not attached"},
@@ -1850,7 +1850,7 @@ argc = ccommand (&argv);
 #endif
 
 /* Make sure that argv has at least 10 elements and that it ends in a NULL pointer */
-targv = calloc (1+MAX(10, argc), sizeof(*targv));
+targv = (char **)calloc (1+MAX(10, argc), sizeof(*targv));
 for (i=0; i<argc; i++)
     targv[i] = argv[i];
 argv = targv;
@@ -2092,7 +2092,7 @@ for (cmdp = sim_vm_cmd; cmdp && (cmdp->name != NULL); cmdp++) {
     if (cmdp->help) {
         if (cmd_cnt >= cmd_size) {
             cmd_size += 20;
-            hlp_cmdp = realloc (hlp_cmdp, sizeof(*hlp_cmdp)*cmd_size);
+            hlp_cmdp = (CTAB **)realloc (hlp_cmdp, sizeof(*hlp_cmdp)*cmd_size);
             }
         hlp_cmdp[cmd_cnt] = cmdp;
         ++cmd_cnt;
@@ -2104,7 +2104,7 @@ for (cmdp = cmd_table; cmdp && (cmdp->name != NULL); cmdp++) {
     if (cmdp->help && (!sim_vm_cmd || !find_ctab (sim_vm_cmd, cmdp->name))) {
         if (cmd_cnt >= cmd_size) {
             cmd_size += 20;
-            hlp_cmdp = realloc (hlp_cmdp, sizeof(*hlp_cmdp)*cmd_size);
+            hlp_cmdp = (CTAB **)realloc (hlp_cmdp, sizeof(*hlp_cmdp)*cmd_size);
             }
         hlp_cmdp[cmd_cnt] = cmdp;
         ++cmd_cnt;
@@ -3178,7 +3178,7 @@ if (!strcmp (gbuf, "NOT")) {                            /* Conditional Inversion
 if (*cptr == '"') {                                     /* quoted string comparison? */
     char op[CBUFSIZE];
     static struct {
-        char *op;
+        const char *op;
         int aval;
         int bval;
         t_bool invert;
@@ -5343,14 +5343,14 @@ return SCPE_OK;
 
 /* Get device display name */
 
-char *sim_dname (DEVICE *dptr)
+const char *sim_dname (DEVICE *dptr)
 {
 return (dptr->lname? dptr->lname: dptr->name);
 }
 
 /* Get unit display name */
 
-char *sim_uname (UNIT *uptr)
+const char *sim_uname (UNIT *uptr)
 {
 DEVICE *d = find_dev_from_unit(uptr);
 static AIO_TLS char uname[CBUFSIZE];
@@ -6984,13 +6984,13 @@ return (c & 0x80) ? 0 : isalnum (c);
 /* get_yn               yes/no question
 
    Inputs:
-        cptr    =       pointer to question
+        ques    =       pointer to question
         deflt   =       default answer
    Outputs:
         result  =       true if yes, false if no
 */
 
-t_stat get_yn (char *ques, t_stat deflt)
+t_stat get_yn (const char *ques, t_stat deflt)
 {
 char cbuf[CBUFSIZE], *cptr;
 
@@ -7185,7 +7185,7 @@ while (iptr[1]) {               /* Skip trailing quote */
             break;
         case 'x':
             if (1) {
-                static char *hex_digits = "0123456789ABCDEF";
+                static const char *hex_digits = "0123456789ABCDEF";
                 const char *c;
 
                 ++iptr;
@@ -7253,7 +7253,7 @@ t_bool single_quote_found = FALSE;
 char quote = '"';
 char *tptr, *optr;
 
-optr = malloc (4*size + 3);
+optr = (char *)malloc (4*size + 3);
 if (optr == NULL)
     return NULL;
 tptr = optr;
@@ -7356,7 +7356,7 @@ return NULL;
 DEVICE *find_unit (const char *cptr, UNIT **uptr)
 {
 uint32 i, u;
-char *nptr;
+const char *nptr;
 const char *tptr;
 t_stat r;
 DEVICE *dptr;
@@ -7592,14 +7592,14 @@ sim_schaptr = NULL;                                     /* no search */
 sim_stabr.logic = sim_staba.logic = SCH_OR;             /* default search params */
 sim_stabr.boolop = sim_staba.boolop = SCH_GE;
 sim_stabr.count = 1;
-sim_stabr.mask = realloc (sim_stabr.mask, sim_emax * sizeof(*sim_stabr.mask));
+sim_stabr.mask = (t_value *)realloc (sim_stabr.mask, sim_emax * sizeof(*sim_stabr.mask));
 memset (sim_stabr.mask, 0, sim_emax * sizeof(*sim_stabr.mask));
-sim_stabr.comp = realloc (sim_stabr.comp, sim_emax * sizeof(*sim_stabr.comp));
+sim_stabr.comp = (t_value *)realloc (sim_stabr.comp, sim_emax * sizeof(*sim_stabr.comp));
 memset (sim_stabr.comp, 0, sim_emax * sizeof(*sim_stabr.comp));
 sim_staba.count = sim_emax;
-sim_staba.mask = realloc (sim_staba.mask, sim_emax * sizeof(*sim_staba.mask));
+sim_staba.mask = (t_value *)realloc (sim_staba.mask, sim_emax * sizeof(*sim_staba.mask));
 memset (sim_staba.mask, 0, sim_emax * sizeof(*sim_staba.mask));
-sim_staba.comp = realloc (sim_staba.comp, sim_emax * sizeof(*sim_staba.comp));
+sim_staba.comp = (t_value *)realloc (sim_staba.comp, sim_emax * sizeof(*sim_staba.comp));
 memset (sim_staba.comp, 0, sim_emax * sizeof(*sim_staba.comp));
 sim_dfdev = sim_dflt_dev;
 sim_dfunit = sim_dfdev->units;
@@ -7658,9 +7658,10 @@ return cptr;
         cp      =       pointer to final '.' if match, NULL if not
 */
 
-char *match_ext (char *fnam, char *ext)
+char *match_ext (char *fnam, const char *ext)
 {
-char *pptr, *fptr, *eptr;
+char *pptr, *fptr;
+const char *eptr;
 
 if ((fnam == NULL) || (ext == NULL))                    /* bad arguments? */
      return NULL;
@@ -7727,9 +7728,9 @@ for (logop = cmpop = -1; (c = *cptr++); ) {             /* loop thru clauses */
     }                                                   /* end for */
 if (schptr->count != 1) {
     free (schptr->mask);
-    schptr->mask = calloc (sim_emax, sizeof(*schptr->mask));
+    schptr->mask = (t_value *)calloc (sim_emax, sizeof(*schptr->mask));
     free (schptr->comp);
-    schptr->comp = calloc (sim_emax, sizeof(*schptr->comp));
+    schptr->comp = (t_value *)calloc (sim_emax, sizeof(*schptr->comp));
     }
 if (logop >= 0) {
     schptr->logic = logop;
@@ -7766,8 +7767,8 @@ const char logstr[] = "|&^", cmpstr[] = "=!><";
 
 if (*cptr == 0)                                         /* check for clause */
     return NULL;
-logval = calloc (sim_emax, sizeof(*logval));
-cmpval = calloc (sim_emax, sizeof(*cmpval));
+logval = (t_value *)calloc (sim_emax, sizeof(*logval));
+cmpval = (t_value *)calloc (sim_emax, sizeof(*cmpval));
 for (logop = cmpop = -1; (c = *cptr++); ) {             /* loop thru clauses */
     if ((sptr = strchr (logstr, c))) {                  /* check for mask */
         logop = (int32)(sptr - logstr);
@@ -7802,9 +7803,9 @@ for (logop = cmpop = -1; (c = *cptr++); ) {             /* loop thru clauses */
 if (schptr->count != (1 - reason)) {
     schptr->count = 1 - reason;
     free (schptr->mask);
-    schptr->mask = calloc (sim_emax, sizeof(*schptr->mask));
+    schptr->mask = (t_value *)calloc (sim_emax, sizeof(*schptr->mask));
     free (schptr->comp);
-    schptr->comp = calloc (sim_emax, sizeof(*schptr->comp));
+    schptr->comp = (t_value *)calloc (sim_emax, sizeof(*schptr->comp));
     }
 if (logop >= 0) {
     schptr->logic = logop;
@@ -7837,7 +7838,7 @@ int32 ret = 0;
 if (schptr == NULL)
     return ret;
 
-val = malloc (schptr->count * sizeof (*values));
+val = (t_value *)malloc (schptr->count * sizeof (*values));
 
 for (i=0; i<(int32)schptr->count; i++) {
     val[i] = values[i];
@@ -8697,7 +8698,7 @@ return sim_brk_act[sim_do_depth] = sim_brk_act_buf[sim_do_depth] = NULL;
 void sim_brk_setact (const char *action)
 {
 if (action) {
-    sim_brk_act_buf[sim_do_depth] = realloc (sim_brk_act_buf[sim_do_depth], strlen (action) + 1);
+    sim_brk_act_buf[sim_do_depth] = (char *)realloc (sim_brk_act_buf[sim_do_depth], strlen (action) + 1);
     strcpy (sim_brk_act_buf[sim_do_depth], action);
     sim_brk_act[sim_do_depth] = sim_brk_act_buf[sim_do_depth];
     }
@@ -8917,7 +8918,7 @@ if (switches & EXP_TYP_REGEX) {
     res = regcomp (&re, (char *)match_buf, REG_EXTENDED | ((switches & EXP_TYP_REGEX_I) ? REG_ICASE : 0));
     if (res) {
         size_t err_size = regerror (res, &re, NULL, 0);
-        char *err_buf = calloc (err_size+1, 1);
+        char *err_buf = (char *)calloc (err_size+1, 1);
 
         regerror (res, &re, err_buf, err_size);
         sim_messagef (SCPE_ARG, "Regular Expression Error: %s\n", err_buf);
@@ -9086,7 +9087,7 @@ for (i=0; i < exp->size; i++) {
         else {
             if (strlen ((char *)exp->buf) != exp->buf_ins) { /* Nul characters in buffer? */
                 size_t off;
-                tstr = malloc (exp->buf_ins + 1);
+                tstr = (char *)malloc (exp->buf_ins + 1);
 
                 tstr[0] = '\0';
                 for (off=0; off < exp->buf_ins; off += 1 + strlen ((char *)&exp->buf[off]))
@@ -9095,7 +9096,7 @@ for (i=0; i < exp->size; i++) {
                 }
             }
         ++regex_checks;
-        matches = calloc ((ep->regex.re_nsub + 1), sizeof(*matches));
+        matches = (regmatch_t *)calloc ((ep->regex.re_nsub + 1), sizeof(*matches));
         if (sim_deb && exp->dptr && (exp->dptr->dctrl & exp->dbit)) {
             char *estr = sim_encode_quoted_string (exp->buf, exp->buf_ins);
             sim_debug (exp->dbit, exp->dptr, "Checking String: %s\n", estr);
@@ -9104,7 +9105,7 @@ for (i=0; i < exp->size; i++) {
             }
         if (!regexec (&ep->regex, cbuf, ep->regex.re_nsub + 1, matches, REG_NOTBOL)) {
             size_t j;
-            char *buf = malloc (1 + exp->buf_ins);
+            char *buf = (char *)malloc (1 + exp->buf_ins);
 
             for (j=0; j<ep->regex.re_nsub + 1; j++) {
                 char env_name[32];
@@ -9239,7 +9240,7 @@ if (snd->extoff != 0) {
     }
 if (snd->insoff+size > snd->bufsize) {
     snd->bufsize = snd->insoff+size;
-    snd->buffer = realloc(snd->buffer, snd->bufsize);
+    snd->buffer = (uint8 *)realloc(snd->buffer, snd->bufsize);
     }
 memcpy(snd->buffer+snd->insoff, data, size);
 snd->insoff += size;
@@ -9361,10 +9362,10 @@ int32 debug_unterm  = 0;
 
 /* Finds debug phrase matching bitmask from from device DEBTAB table */
 
-static char *get_dbg_verb (uint32 dbits, DEVICE* dptr)
+static const char *get_dbg_verb (uint32 dbits, DEVICE* dptr)
 {
-static char *debtab_none    = "DEBTAB_ISNULL";
-static char *debtab_nomatch = "DEBTAB_NOMATCH";
+static const char *debtab_none    = "DEBTAB_ISNULL";
+static const char *debtab_nomatch = "DEBTAB_NOMATCH";
 int32 offset = 0;
 
 if (dptr->debflags == 0)
@@ -9384,7 +9385,7 @@ return debtab_nomatch;
 
 static const char *sim_debug_prefix (uint32 dbits, DEVICE* dptr)
 {
-char* debug_type = get_dbg_verb (dbits, dptr);
+const char* debug_type = get_dbg_verb (dbits, dptr);
 char tim_t[32] = "";
 char tim_a[32] = "";
 char pc_s[64] = "";
@@ -9442,7 +9443,7 @@ for (i = fields-1; i >= 0; i--) {                   /* print xlation, transition
         fprintf(stream, "%s%c ", bitdefs[i].name, debug_bstates[off]);
         }
     else {
-        char *delta = "";
+        const char *delta = "";
 
         mask = 0xFFFFFFFF >> (32-bitdefs[i].width);
         value = (uint32)((after >> bitdefs[i].offset) & mask);
@@ -10279,7 +10280,7 @@ TOPIC *topic = &top;
 int failed;
 size_t match;
 size_t i;
-char *p;
+const char *p;
 t_bool flat_help = FALSE;
 char cbuf [CBUFSIZE], gbuf[CBUFSIZE];
 
@@ -10539,7 +10540,7 @@ fp = sim_fopen (helpfile, "r");
 if (fp == NULL) {
     if (sim_argv && *sim_argv[0]) {
         char fbuf[(4*PATH_MAX)+1]; /* PATH_MAX is ridiculously small on some platforms */
-        char *d = NULL;
+        const char *d = NULL;
 
         /* Try to find a path from argv[0].  This won't always
          * work (one reason files are probably not a good idea),
diff --git a/scp.h b/scp.h
index 80bfe084..e1f479d7 100644
--- a/scp.h
+++ b/scp.h
@@ -122,9 +122,9 @@ t_stat assign_device (DEVICE *dptr, char *cptr);
 t_stat deassign_device (DEVICE *dptr);
 t_stat reset_all (uint32 start_device);
 t_stat reset_all_p (uint32 start_device);
-char *sim_dname (DEVICE *dptr);
-char *sim_uname (UNIT *dptr);
-t_stat get_yn (char *ques, t_stat deflt);
+const char *sim_dname (DEVICE *dptr);
+const char *sim_uname (UNIT *dptr);
+t_stat get_yn (const char *ques, t_stat deflt);
 int sim_isspace (char c);
 int sim_islower (char c);
 int sim_isalpha (char c);
@@ -177,7 +177,7 @@ t_stat sim_exp_clrall (EXPECT *exp);
 t_stat sim_exp_show (FILE *st, EXPECT *exp, const char *match);
 t_stat sim_exp_showall (FILE *st, EXPECT *exp);
 t_stat sim_exp_check (EXPECT *exp, uint8 data);
-char *match_ext (char *fnam, char *ext);
+char *match_ext (char *fnam, const char *ext);
 t_stat show_version (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
 t_stat set_dev_debug (DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
 t_stat show_dev_debug (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
diff --git a/sim_BuildROMs.c b/sim_BuildROMs.c
index 2a765044..4b3e4d73 100644
--- a/sim_BuildROMs.c
+++ b/sim_BuildROMs.c
@@ -38,13 +38,13 @@
       =======================================================================================
 */
 struct ROM_File_Descriptor {
-    char *BinaryName;                   char *IncludeFileName;   size_t expected_size; unsigned int checksum;  char *ArrayName;} ROMs[] = {
-   {"VAX/ka655x.bin",                   "VAX/vax_ka655x_bin.h",                131072,            0xFF7673B6, "vax_ka655x_bin"},
-   {"VAX/ka620.bin",                    "VAX/vax_ka620_bin.h",                  65536,            0xFF7F930F, "vax_ka620_bin"},
-   {"VAX/ka630.bin",                    "VAX/vax_ka630_bin.h",                  65536,            0xFF7F73EF, "vax_ka630_bin"},
-   {"VAX/ka610.bin",                    "VAX/vax_ka610_bin.h",                  16384,            0xFFEF3312, "vax_ka610_bin"},
-   {"VAX/vmb.exe",                      "VAX/vax_vmb_exe.h",                    44544,            0xFFC014BB, "vax_vmb_exe"},
-   {"swtp6800/swtp6800/swtbug.bin",     "swtp6800/swtp6800/swtp_swtbug_bin.h",   1024,            0xFFFE4FBC, "swtp_swtbug_bin"},
+    const char *BinaryName;             const char *IncludeFileName; size_t expected_size; unsigned int checksum;  const char *ArrayName;} ROMs[] = {
+   {"VAX/ka655x.bin",                   "VAX/vax_ka655x_bin.h",                    131072,            0xFF7673B6,        "vax_ka655x_bin"},
+   {"VAX/ka620.bin",                    "VAX/vax_ka620_bin.h",                      65536,            0xFF7F930F,        "vax_ka620_bin"},
+   {"VAX/ka630.bin",                    "VAX/vax_ka630_bin.h",                      65536,            0xFF7F73EF,        "vax_ka630_bin"},
+   {"VAX/ka610.bin",                    "VAX/vax_ka610_bin.h",                      16384,            0xFFEF3312,        "vax_ka610_bin"},
+   {"VAX/vmb.exe",                      "VAX/vax_vmb_exe.h",                        44544,            0xFFC014BB,        "vax_vmb_exe"},
+   {"swtp6800/swtp6800/swtbug.bin",     "swtp6800/swtp6800/swtp_swtbug_bin.h",       1024,            0xFFFE4FBC,        "swtp_swtbug_bin"},
    };
 
 
@@ -144,6 +144,7 @@ unsigned char *ROMData = NULL;
 unsigned int checksum = 0;
 char *c;
 int i;
+char cleaned_rom_filename[512];
 char include_filename[512];
 char array_name[512];
 
@@ -167,9 +168,11 @@ fclose (rFile);
 for (i=0; i<statb.st_size; ++i)
     checksum += ROMData[i];
 checksum = ~checksum;
-while ((c = strchr (rom_filename, '\\')))
+strncpy (cleaned_rom_filename, rom_filename, sizeof(cleaned_rom_filename)-2);
+cleaned_rom_filename[sizeof(cleaned_rom_filename)-1] = '\0';
+while ((c = strchr (cleaned_rom_filename, '\\')))
     *c = '/';
-strcpy (array_name, rom_filename);
+strcpy (array_name, cleaned_rom_filename);
 for (c=array_name; *c; ++c)
     if (isupper(*c))
         *c = (char)tolower(*c);
@@ -177,7 +180,7 @@ if ((c = strchr (array_name, '.')))
     *c = '_';
 if ((c = strchr (array_name, '/')))
     *c = '_';
-sprintf (include_filename, "%s.h", rom_filename);
+sprintf (include_filename, "%s.h", cleaned_rom_filename);
 if ((c = strrchr (include_filename, '/')))
     sprintf (c+1, "%s.h", array_name);
 else
diff --git a/sim_defs.h b/sim_defs.h
index d13e0a67..f9651cd2 100644
--- a/sim_defs.h
+++ b/sim_defs.h
@@ -376,7 +376,7 @@ typedef uint32          t_addr;
 /* Device data structure */
 
 struct sim_device {
-    char                *name;                          /* name */
+    const char          *name;                          /* name */
     struct sim_unit     *units;                         /* units */
     struct sim_reg      *registers;                     /* registers */
     struct sim_mtab     *modifiers;                     /* modifiers */
@@ -404,13 +404,13 @@ struct sim_device {
                                                         /* mem size routine */
     char                *lname;                         /* logical name */
     t_stat              (*help)(FILE *st, struct sim_device *dptr,
-                            struct sim_unit *uptr, int32 flag, char *cptr); 
+                            struct sim_unit *uptr, int32 flag, const char *cptr); 
                                                         /* help */
     t_stat              (*attach_help)(FILE *st, struct sim_device *dptr,
-                            struct sim_unit *uptr, int32 flag, char *cptr);
+                            struct sim_unit *uptr, int32 flag, const char *cptr);
                                                         /* attach help */
     void *help_ctx;                                     /* Context available to help routines */
-    char                *(*description)(struct sim_device *dptr);
+    const char          *(*description)(struct sim_device *dptr);
                                                         /* Device Description */
     };
 
@@ -540,7 +540,7 @@ struct sim_unit {
 #define UNIT_S_DF_TAPE  3               /* Bits Reserved for Tape Density */
 
 struct sim_bitfield {
-    char            *name;                              /* field name */
+    const char      *name;                              /* field name */
     uint32          offset;                             /* starting bit */
     uint32          width;                              /* width */
     const char      **valuenames;                       /* map of values to strings */
@@ -550,13 +550,13 @@ struct sim_bitfield {
 /* Register data structure */
 
 struct sim_reg {
-    char                *name;                          /* name */
+    const char          *name;                          /* name */
     void                *loc;                           /* location */
     uint32              radix;                          /* radix */
     uint32              width;                          /* width */
     uint32              offset;                         /* starting bit */
     uint32              depth;                          /* save depth */
-    char                *desc;                          /* description */
+    const char          *desc;                          /* description */
     struct sim_bitfield *fields;                        /* bit fields */
     uint32              flags;                          /* flags */
     uint32              qptr;                           /* circ q ptr */
@@ -576,7 +576,7 @@ struct sim_reg {
 /* Command tables, base and alternate formats */
 
 struct sim_ctab {
-    char                *name;                          /* name */
+    const char          *name;                          /* name */
     t_stat              (*action)(int32 flag, char *cptr);
                                                         /* action routine */
     int32               arg;                            /* argument */
@@ -587,19 +587,19 @@ struct sim_ctab {
     };
 
 struct sim_c1tab {
-    char                *name;                          /* name */
+    const char          *name;                          /* name */
     t_stat              (*action)(struct sim_device *dptr, struct sim_unit *uptr,
                             int32 flag, char *cptr);    /* action routine */
     int32               arg;                            /* argument */
-    char                *help;                          /* help string */
+    const char          *help;                          /* help string */
     };
 
 struct sim_shtab {
-    char                *name;                          /* name */
+    const char          *name;                          /* name */
     t_stat              (*action)(FILE *st, struct sim_device *dptr,
                             struct sim_unit *uptr, int32 flag, char *cptr);
     int32               arg;                            /* argument */
-    char                *help;                          /* help string */
+    const char          *help;                          /* help string */
     };
 
 /* Modifier table - only extended entries have disp, reg, or flags */
@@ -607,8 +607,8 @@ struct sim_shtab {
 struct sim_mtab {
     uint32              mask;                           /* mask */
     uint32              match;                          /* match */
-    char                *pstring;                       /* print string */
-    char                *mstring;                       /* match string */
+    const char          *pstring;                       /* print string */
+    const char          *mstring;                       /* match string */
     t_stat              (*valid)(struct sim_unit *up, int32 v, char *cp, void *dp);
                                                         /* validation routine */
     t_stat              (*disp)(FILE *st, struct sim_unit *up, int32 v, void *dp);
@@ -616,7 +616,7 @@ struct sim_mtab {
     void                *desc;                          /* value descriptor */
                                                         /* REG * if MTAB_VAL */
                                                         /* int * if not */
-    char                *help;                          /* help string */
+    const char          *help;                          /* help string */
     };
 
 
@@ -705,9 +705,9 @@ struct sim_send {
 /* Debug table */
 
 struct sim_debtab {
-    char                *name;                          /* control name */
+    const char          *name;                          /* control name */
     uint32              mask;                           /* control bit */
-    char                *desc;                          /* description */
+    const char          *desc;                          /* description */
     };
 
 /* Deprecated Debug macros.  Use sim_debug() */
@@ -835,7 +835,7 @@ typedef struct sim_bitfield BITFIELD;
 /* This replaces any references to "assert()" which should never be invoked */
 /* with an expression which causes side effects (i.e. must be executed for */
 /* the program to work correctly) */
-#define ASSURE(_Expression) if (!(_Expression)) {char *_exp = #_Expression; char *_file = __FILE__;                                 \
+#define ASSURE(_Expression) if (!(_Expression)) {const char *_exp = #_Expression; const char *_file = __FILE__;                                 \
                                                  fprintf(stderr, "%s failed at %s line %d\n", _exp, _file, __LINE__);               \
                                                  if (sim_log) fprintf(sim_log, "%s failed at %s line %d\n", _exp, _file, __LINE__); \
                                                  if (sim_deb) fprintf(sim_deb, "%s failed at %s line %d\n", _exp, _file, __LINE__); \
diff --git a/sim_disk.c b/sim_disk.c
index b9511b53..992e3a42 100644
--- a/sim_disk.c
+++ b/sim_disk.c
@@ -292,7 +292,7 @@ static char *HostPathToVhdPath (const char *szHostPath, char *szVhdPath, size_t
 static char *VhdPathToHostPath (const char *szVhdPath, char *szHostPath, size_t HostPathSize);
 
 struct sim_disk_fmt {
-    char                *name;                          /* name */
+    const char          *name;                          /* name */
     int32               uflags;                         /* unit flags */
     int32               fmtval;                         /* Format type value */
     t_stat              (*impl_fnc)(void);              /* Implemented Test Function */
@@ -367,7 +367,7 @@ return SCPE_OK;
 t_stat sim_disk_show_capac (FILE *st, UNIT *uptr, int32 val, void *desc)
 {
 struct disk_context *ctx = (struct disk_context *)uptr->disk_ctx;
-char *cap_units = "B";
+const char *cap_units = "B";
 DEVICE *dptr = find_dev_from_unit (uptr);
 t_offset capac = ((t_offset)uptr->capac)*((dptr->flags & DEV_SECTORS) ? 512 : 1);
 
@@ -1215,7 +1215,7 @@ if (close_function (fileref) == EOF)
 return SCPE_OK;
 }
 
-t_stat sim_disk_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat sim_disk_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "%s Disk Attach Help\n\n", dptr->name);
 
@@ -1443,7 +1443,7 @@ for (i = 4; i < wds; i++)
     buf[i] = 0177777u;
 da = (uptr->capac*((dptr->flags & DEV_SECTORS) ? 512 : 1)) - (sec * wds);
 for (i = 0; (i < sec) && (i < 10); i++, da += wds)
-    if (sim_disk_wrsect (uptr, (t_lba)(da/wds), (void *)buf, NULL, 1)) {
+    if (sim_disk_wrsect (uptr, (t_lba)(da/wds), (uint8 *)buf, NULL, 1)) {
         free (buf);
         return SCPE_IOERR;
         }
diff --git a/sim_disk.h b/sim_disk.h
index acc15771..dbff7017 100644
--- a/sim_disk.h
+++ b/sim_disk.h
@@ -67,7 +67,7 @@ typedef void (*DISK_PCALLBACK)(UNIT *unit, t_stat status);
 t_stat sim_disk_attach (UNIT *uptr, char *cptr, size_t sector_size, size_t xfer_element_size, t_bool dontautosize, 
                         uint32 debugbit, const char *drivetype, uint32 pdp11_tracksize, int completion_delay);
 t_stat sim_disk_detach (UNIT *uptr);
-t_stat sim_disk_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+t_stat sim_disk_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat sim_disk_rdsect (UNIT *uptr, t_lba lba, uint8 *buf, t_seccnt *sectsread, t_seccnt sects);
 t_stat sim_disk_rdsect_a (UNIT *uptr, t_lba lba, uint8 *buf, t_seccnt *sectsread, t_seccnt sects, DISK_PCALLBACK callback);
 t_stat sim_disk_wrsect (UNIT *uptr, t_lba lba, uint8 *buf, t_seccnt *sectswritten, t_seccnt sects);
diff --git a/sim_ether.c b/sim_ether.c
index f7ec4c3f..91788d34 100644
--- a/sim_ether.c
+++ b/sim_ether.c
@@ -511,7 +511,7 @@ void eth_setcrc(ETH_DEV* dev, int need_crc)
   dev->need_crc = need_crc;
 }
 
-void eth_packet_trace_ex(ETH_DEV* dev, const uint8 *msg, int len, char* txt, int detail, uint32 reason)
+void eth_packet_trace_ex(ETH_DEV* dev, const uint8 *msg, int len, const char* txt, int detail, uint32 reason)
 {
   if (dev->dptr->dctrl & reason) {
     char src[20];
@@ -557,12 +557,12 @@ void eth_packet_trace_ex(ETH_DEV* dev, const uint8 *msg, int len, char* txt, int
   }
 }
 
-void eth_packet_trace(ETH_DEV* dev, const uint8 *msg, int len, char* txt)
+void eth_packet_trace(ETH_DEV* dev, const uint8 *msg, int len, const char* txt)
 {
   eth_packet_trace_ex(dev, msg, len, txt, 0, dev->dbit);
 }
 
-void eth_packet_trace_detail(ETH_DEV* dev, const uint8 *msg, int len, char* txt)
+void eth_packet_trace_detail(ETH_DEV* dev, const uint8 *msg, int len, const char* txt)
 {
   eth_packet_trace_ex(dev, msg, len, txt, 1     , dev->dbit);
 }
@@ -851,7 +851,7 @@ t_stat eth_open(ETH_DEV* dev, char* name, DEVICE* dptr, uint32 dbit)
   {return SCPE_NOFNC;}
 t_stat eth_close (ETH_DEV* dev)
   {return SCPE_NOFNC;}
-t_stat eth_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat eth_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
   {
   fprintf (st, "%s attach help\n\n", dptr->name);
   fprintf (st, "This simulator was not built with ethernet device support\n");
@@ -958,7 +958,7 @@ static HINSTANCE hLib = 0;                      /* handle to DLL */
 static void *hLib = 0;                      /* handle to Library */
 #endif
 static int lib_loaded = 0;                      /* 0=not loaded, 1=loaded, 2=library load failed, 3=Func load failed */
-static char* lib_name =
+static const char* lib_name =
 #if defined(_WIN32) || defined(__CYGWIN__)
                           "wpcap.dll";
 #elif defined(__APPLE__)
@@ -968,7 +968,7 @@ static char* lib_name =
 #define __STR(tok) __STR_QUOTE(tok)
                           "libpcap." __STR(HAVE_DLOPEN);
 #endif
-static char* no_pcap = 
+static const char* no_pcap = 
 #if defined(_WIN32) || defined(__CYGWIN__)
                           "wpcap load failure";
 #else
@@ -1003,7 +1003,7 @@ static char*   (*p_pcap_lib_version) (void);
 /* load function pointer from DLL */
 typedef int (*_func)();
 
-static void load_function(char* function, _func* func_ptr) {
+static void load_function(const char* function, _func* func_ptr) {
 #ifdef _WIN32
     *func_ptr = (_func)((size_t)GetProcAddress(hLib, function));
 #else
@@ -1441,7 +1441,7 @@ static void eth_get_nic_hw_addr(ETH_DEV* dev, char *devname)
     char command[1024];
     FILE *f;
     int i;
-    char *patterns[] = {
+    const char *patterns[] = {
         "grep [0-9a-fA-F][0-9a-fA-F]:[0-9a-fA-F][0-9a-fA-F]:[0-9a-fA-F][0-9a-fA-F]:[0-9a-fA-F][0-9a-fA-F]:[0-9a-fA-F][0-9a-fA-F]:[0-9a-fA-F][0-9a-fA-F]",
         "egrep [0-9a-fA-F]?[0-9a-fA-F]:[0-9a-fA-F]?[0-9a-fA-F]:[0-9a-fA-F]?[0-9a-fA-F]:[0-9a-fA-F]?[0-9a-fA-F]:[0-9a-fA-F]?[0-9a-fA-F]:[0-9a-fA-F]?[0-9a-fA-F]",
         NULL};
@@ -2160,7 +2160,7 @@ _eth_remove_from_open_list (dev);
 return SCPE_OK;
 }
 
-t_stat eth_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat eth_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "%s attach help\n\n", dptr->name);
 fprintf (st, "   sim> SHOW ETHERNET\n");
@@ -2333,7 +2333,7 @@ static void
 _eth_error(ETH_DEV* dev, const char* where)
 {
 char msg[64];
-char *netname = "";
+const char *netname = "";
 time_t now;
 
 time(&now);
@@ -3490,21 +3490,21 @@ if (dev->eth_api == ETH_API_PCAP) {
   if (pcap_lookupnet(dev->name, &bpf_subnet, &bpf_netmask, errbuf)<0)
     bpf_netmask = 0;
   /* compile filter string */
-  if ((status = pcap_compile(dev->handle, &bpf, buf, 1, bpf_netmask)) < 0) {
-    sprintf(errbuf, "%s", pcap_geterr(dev->handle));
+  if ((status = pcap_compile((pcap_t*)dev->handle, &bpf, buf, 1, bpf_netmask)) < 0) {
+    sprintf(errbuf, "%s", pcap_geterr((pcap_t*)dev->handle));
     sim_printf("Eth: pcap_compile error: %s\r\n", errbuf);
     /* show erroneous BPF string */
     sim_printf ("Eth: BPF string is: |%s|\r\n", buf);
     }
   else {
     /* apply compiled filter string */
-    if ((status = pcap_setfilter(dev->handle, &bpf)) < 0) {
-      sprintf(errbuf, "%s", pcap_geterr(dev->handle));
+    if ((status = pcap_setfilter((pcap_t*)dev->handle, &bpf)) < 0) {
+      sprintf(errbuf, "%s", pcap_geterr((pcap_t*)dev->handle));
       sim_printf("Eth: pcap_setfilter error: %s\r\n", errbuf);
       }
     else {
       /* Save BPF filter string */
-      dev->bpf_filter = realloc(dev->bpf_filter, 1 + strlen(buf));
+      dev->bpf_filter = (char *)realloc(dev->bpf_filter, 1 + strlen(buf));
       strcpy (dev->bpf_filter, buf);
 #ifdef USE_SETNONBLOCK
       /* set file non-blocking */
diff --git a/sim_ether.h b/sim_ether.h
index 875651d3..e0460107 100644
--- a/sim_ether.h
+++ b/sim_ether.h
@@ -320,7 +320,7 @@ typedef struct eth_device  ETH_DEV;
 t_stat eth_open   (ETH_DEV* dev, char* name,            /* open ethernet interface */
                    DEVICE* dptr, uint32 dbit);
 t_stat eth_close  (ETH_DEV* dev);                       /* close ethernet interface */
-t_stat eth_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+t_stat eth_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat eth_write  (ETH_DEV* dev, ETH_PACK* packet,      /* write sychronous packet; */
                    ETH_PCALLBACK routine);              /*  callback when done */
 int eth_read      (ETH_DEV* dev, ETH_PACK* packet,      /* read single packet; */
@@ -343,8 +343,8 @@ t_stat eth_clr_async (ETH_DEV* dev);                    /* set read behavior to
 t_stat eth_set_throttle (ETH_DEV* dev, uint32 time, uint32 burst, uint32 delay); /* set transmit throttle parameters */
 uint32 eth_crc32(uint32 crc, const void* vbuf, size_t len); /* Compute Ethernet Autodin II CRC for buffer */
 
-void eth_packet_trace (ETH_DEV* dev, const uint8 *msg, int len, char* txt); /* trace ethernet packet header+crc */
-void eth_packet_trace_ex (ETH_DEV* dev, const uint8 *msg, int len, char* txt, int detail, uint32 reason); /* trace ethernet packet */
+void eth_packet_trace (ETH_DEV* dev, const uint8 *msg, int len, const char* txt); /* trace ethernet packet header+crc */
+void eth_packet_trace_ex (ETH_DEV* dev, const uint8 *msg, int len, const char* txt, int detail, uint32 reason); /* trace ethernet packet */
 t_stat eth_show (FILE* st, UNIT* uptr,                  /* show ethernet devices */
                  int32 val, void* desc);
 t_stat eth_show_devices (FILE* st, DEVICE *dptr,        /* show ethernet devices */
diff --git a/sim_serial.c b/sim_serial.c
index 317ebefc..bb184e65 100644
--- a/sim_serial.c
+++ b/sim_serial.c
@@ -213,7 +213,7 @@ for (i=0; i<serial_open_device_count; ++i)
    an error message if desired, rather than printing this generic error message.
 */
 
-static void sim_error_serial (char *routine, int error)
+static void sim_error_serial (const char *routine, int error)
 {
 sim_printf ("Serial: %s fails with error %d\n", routine, error);
 return;
@@ -391,7 +391,7 @@ SERHANDLE sim_open_serial (char *name, TMLN *lp, t_stat *stat)
 char temp1[1024], devname [1024];
 char *savname = name;
 SERHANDLE port = INVALID_HANDLE;
-char *config;
+const char *config;
 t_stat status;
 
 config = get_glyph_nc (name, devname, ';');             /* separate port name from optional config params */
@@ -1282,7 +1282,7 @@ else {                                                      /* read succeeded */
     remaining = read_count - 1;                             /* stop search one char from end of string */
 
     while (remaining > 0 &&                                 /* still characters to search? */
-           (bptr = memchr (cptr, '\377', remaining))) {     /* search for start of PARMRK sequence */
+           (bptr = (char*)memchr (cptr, '\377', remaining))) {/* search for start of PARMRK sequence */
         remaining = remaining - (bptr - cptr) - 1;          /* calc characters remaining */
 
         if (*(bptr + 1) == '\377') {                        /* is it a \377 \377 sequence? */
diff --git a/sim_sock.c b/sim_sock.c
index e815a59c..477caec9 100644
--- a/sim_sock.c
+++ b/sim_sock.c
@@ -151,7 +151,7 @@ static struct sock_errors {
     };
 
 
-char *sim_get_err_sock (const char *emsg)
+const char *sim_get_err_sock (const char *emsg)
 {
 int err = WSAGetLastError ();
 int i;
diff --git a/sim_sock.h b/sim_sock.h
index 6d063194..56c57356 100644
--- a/sim_sock.h
+++ b/sim_sock.h
@@ -126,7 +126,7 @@ int sim_check_conn (SOCKET sock, int rd);
 int sim_read_sock (SOCKET sock, char *buf, int nbytes);
 int sim_write_sock (SOCKET sock, const char *msg, int nbytes);
 void sim_close_sock (SOCKET sock);
-char *sim_get_err_sock (const char *emsg);
+const char *sim_get_err_sock (const char *emsg);
 SOCKET sim_err_sock (SOCKET sock, const char *emsg);
 int sim_getnames_sock (SOCKET sock, char **socknamebuf, char **peernamebuf);
 void sim_init_sock (void);
diff --git a/sim_tape.c b/sim_tape.c
index c63d9660..96c536f3 100644
--- a/sim_tape.c
+++ b/sim_tape.c
@@ -97,7 +97,7 @@
 #endif
 
 struct sim_tape_fmt {
-    char                *name;                          /* name */
+    const char          *name;                          /* name */
     int32               uflags;                         /* unit flags */
     t_addr              bot;                            /* bot test */
     };
@@ -533,7 +533,7 @@ uptr->io_flush = NULL;
 return SCPE_OK;
 }
 
-t_stat sim_tape_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat sim_tape_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 fprintf (st, "%s Tape Attach Help\n\n", dptr->name);
 if (0 == (uptr-dptr->units)) {
diff --git a/sim_tape.h b/sim_tape.h
index 920feda8..10831d27 100644
--- a/sim_tape.h
+++ b/sim_tape.h
@@ -151,7 +151,7 @@ typedef void (*TAPE_PCALLBACK)(UNIT *unit, t_stat status);
 t_stat sim_tape_attach_ex (UNIT *uptr, char *cptr, uint32 dbit, int completion_delay);
 t_stat sim_tape_attach (UNIT *uptr, char *cptr);
 t_stat sim_tape_detach (UNIT *uptr);
-t_stat sim_tape_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+t_stat sim_tape_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 t_stat sim_tape_rdrecf (UNIT *uptr, uint8 *buf, t_mtrlnt *bc, t_mtrlnt max);
 t_stat sim_tape_rdrecf_a (UNIT *uptr, uint8 *buf, t_mtrlnt *bc, t_mtrlnt max, TAPE_PCALLBACK callback);
 t_stat sim_tape_rdrecr (UNIT *uptr, uint8 *buf, t_mtrlnt *bc, t_mtrlnt max);
diff --git a/sim_tmxr.c b/sim_tmxr.c
index e679e3dd..389f2d16 100644
--- a/sim_tmxr.c
+++ b/sim_tmxr.c
@@ -3643,7 +3643,7 @@ return sim_clock_coschedule_tmr (uptr, tmr, interval);
 
 /* Generic Multiplexer attach help */
 
-t_stat tmxr_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr)
+t_stat tmxr_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
 TMXR *mux = (TMXR *)dptr->help_ctx;
 t_bool single_line = FALSE;               /* default to Multi-Line help */
@@ -4374,7 +4374,7 @@ return SCPE_OK;
 
 static struct {
     u_char value;
-    char *name;
+    const char *name;
     } tn_chars[] =
     {
         {TN_IAC,    "TN_IAC"},                /* protocol delim */
diff --git a/sim_tmxr.h b/sim_tmxr.h
index 54734c50..9d795331 100644
--- a/sim_tmxr.h
+++ b/sim_tmxr.h
@@ -206,7 +206,7 @@ t_stat tmxr_close_master (TMXR *mp);
 t_stat tmxr_connection_poll_interval (TMXR *mp, uint32 seconds);
 t_stat tmxr_attach_ex (TMXR *mp, UNIT *uptr, char *cptr, t_bool async);
 t_stat tmxr_detach (TMXR *mp, UNIT *uptr);
-t_stat tmxr_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, char *cptr);
+t_stat tmxr_attach_help(FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
 char *tmxr_line_attach_string(TMLN *lp);
 t_stat tmxr_set_modem_control_passthru (TMXR *mp);
 t_stat tmxr_clear_modem_control_passthru (TMXR *mp);
diff --git a/sim_video.c b/sim_video.c
index 9416a01c..7d11d54d 100644
--- a/sim_video.c
+++ b/sim_video.c
@@ -1183,9 +1183,9 @@ static char *eventtypes[] = {
     ""
     };
 #else
-static char *eventtypes[SDL_LASTEVENT];
+static const char *eventtypes[SDL_LASTEVENT];
 #endif
-static char *windoweventtypes[256];
+static const char *windoweventtypes[256];
 static t_bool initialized = FALSE;
 
 if (!initialized) {
@@ -1604,7 +1604,7 @@ for (i = 0; i < SDL_GetNumRenderDrivers(); ++i) {
         }
     else {
         uint32 j, k;
-        static struct {uint32 format; char *name;} PixelFormats[] = {
+        static struct {uint32 format; const char *name;} PixelFormats[] = {
             {SDL_PIXELFORMAT_INDEX1LSB,     "Index1LSB"},
             {SDL_PIXELFORMAT_INDEX1MSB,     "Index1MSB"},
             {SDL_PIXELFORMAT_INDEX4LSB,     "Index4LSB"},
@@ -1677,7 +1677,7 @@ if (vid_active) {
     fprintf (st, "  Currently Active Renderer: %s\n", info.name);
     }
 if (1) {
-    static char *hints[] = {
+    static const char *hints[] = {
 #if defined (SDL_HINT_FRAMEBUFFER_ACCELERATION)
                 SDL_HINT_FRAMEBUFFER_ACCELERATION   ,
 #endif
@@ -1889,5 +1889,5 @@ return SCPE_OK;
 #endif /* defined(HAVE_LIBSDL) */
 
 #else /* !defined(USE_SIM_VIDEO) */
-static char *dummy_declaration = "Something to compile";
+static const char *dummy_declaration = "Something to compile";
 #endif /* defined(USE_SIM_VIDEO) */