I1620: Updated Simulator

- added deferred IO and RELEASE button simulation
- added SET TTY 1DIGIT
- added SET LPT NOFF
- numerous fixes from Tom McBride, Bob Armstrong, and Dave Wise

I1620/i1620_cd.c

@@ -26,6 +26,7 @@
    cdr          1622 card reader
    cdp          1622 card punch
 
+   23-Jun-17    RMS     Unattached error does not set RDCHK/WRCHK
    09-Mar-17    RMS     Guardbanded translation table lookups (COVERITY)
    31-Jan-15    TFM     Changes to translation tables (Tom McBride)
    10-Dec-13    RMS     Fixed WA card punch translations (Bob Armstrong)
@@ -339,10 +340,8 @@ t_stat cdr_read (void)
 int32 i;
 
 ind[IN_LAST] = 0;                                       /* clear last card */
-if ((cdr_unit.flags & UNIT_ATT) == 0) {                 /* attached? */
+if ((cdr_unit.flags & UNIT_ATT) == 0)                   /* attached? */
-    ind[IN_RDCHK] = 1;                                  /* no, error */
     return SCPE_UNATT;
-    }
 
 for (i = 0; i < CD_LEN + 2; i++)                        /* clear buffer */
     cdr_buf[i] = ' ';
@@ -520,10 +519,8 @@ return SCPE_OK;
 
 t_stat cdp_write (uint32 len)
 {
-if ((cdp_unit.flags & UNIT_ATT) == 0) {                 /* attached? */
+if ((cdp_unit.flags & UNIT_ATT) == 0)                   /* attached? */
-    ind[IN_WRCHK] = 1;                                  /* no, error */
     return SCPE_UNATT;
-    }
 
 while ((len > 0) && (cdp_buf[len - 1] == ' '))          /* trim spaces */
     --len;

I1620/i1620_cpu.c

@@ -26,6 +26,8 @@
    This CPU module incorporates code and comments from the 1620 simulator by
    Geoff Kuenning, with his permission.
 
+   23-Jun-17    RMS     BS should not enable indexing unless configured
+   15-Jun-17    RMS     Added more information to IO in progress message
    26-May-17    RMS     Added deferred IO mode for slow devices
    20-May-17    RMS     Changed to commit PC on certain stops
                         Added SET CPU RELEASE command
@@ -94,6 +96,7 @@
 
    cpuio_mode           set if IO in progress
    cpuio_opc            saved IO opcode
+   cpuio_dev            saved IO device number
    cpuio_cnt            character counter; increments
    PAR                  P address; increments
 
@@ -152,6 +155,7 @@ uint32 io_stop = 1;                                     /* I/O stop */
 uint32 ar_stop = 1;                                     /* arith stop */
 uint32 cpuio_inp = 0;                                   /* IO in progress */
 uint32 cpuio_opc = 0;
+uint32 cpuio_dev = 0;
 uint32 cpuio_cnt = 0;
 int32 ind_max = 16;                                     /* iadr nest limit */
 uint16 pcq[PCQ_SIZE] = { 0 };                           /* PC queue */
@@ -249,6 +253,7 @@ REG cpu_reg[] = {
     { FLDATAD (IOSTOP, io_stop, 0, "I/O stop") },
     { FLDATAD (IOINP, cpuio_inp, 0, "IO in progress"), REG_RO },
     { DRDATAD (IOOPC, cpuio_opc, 6, "IO opcode"), REG_RO },
+    { DRDATAD (IODEV, cpuio_dev, 7, "IO device"), REG_RO },
     { DRDATA (IOCNT, cpuio_cnt, 16), REG_RO },
     { BRDATA (IND, ind, 10, 1, NUM_IND) },
     { FLDATAD (IAE, iae, 0, "indirect address enable (Model 2 only)") },
@@ -960,7 +965,7 @@ while (reason == SCPE_OK) {                             /* loop until halted */
             }
         break;
 
-/* Branch and select - P is valid */
+/* Branch and select - P is valid - Model 2 only */
 
     case OP_BS:
         t = M[ADDR_A (saved_PC, I_SEL)] & DIGIT;        /* get select */
@@ -969,9 +974,11 @@ while (reason == SCPE_OK) {                             /* loop until halted */
             idxe = idxb = 0;                            /* indexing off */
             break;
         case 1:
+            if ((cpu_unit.flags & IF_IDX) != 0)         /* indexing present? */
                 idxe = 1; idxb = 0;                     /* index band A */
             break;
         case 2:
+            if ((cpu_unit.flags & IF_IDX) != 0)         /* indexing present? */
                 idxe = idxb = 1;                        /* index band B */
             break;
         case 8:
@@ -1111,8 +1118,13 @@ for (i = 0; commit_pc[i] != 0; i++) {                   /* check stop code */
 actual_PC = PC;                                         /* save cur PC for RLS */
 pcq_r->qptr = pcq_p;                                    /* update pc q ptr */
 upd_ind ();
-if (cpuio_inp != 0)                                     /* flag IO in progress */
+if (cpuio_inp != 0) {                                   /* flag IO in progress */
-    sim_printf ("\r\nIO in progress");
+    const char *opstr = opc_lookup (cpuio_opc, cpuio_dev * 100, NULL);
+
+    if (opstr != NULL)
+        sim_printf ("\r\nIO in progress (%s %05d)", opstr, PAR);
+    else sim_printf ("\r\nIO in progress (%02d %05d,%05d)", cpuio_opc, PAR, cpuio_dev * 100);
+    }
 return reason;
 }
 
@@ -2164,10 +2176,11 @@ return SCPE_OK;
 
 /* Set and clear IO in progress */
 
-t_stat cpuio_set_inp (uint32 op, UNIT *uptr)
+t_stat cpuio_set_inp (uint32 op, uint32 dev, UNIT *uptr)
 {
 cpuio_inp = 1;
 cpuio_opc = op;
+cpuio_dev = dev;
 cpuio_cnt = 0;
 if (uptr != NULL)
     DEFIO_ACTIVATE_ABS (uptr);
@@ -2178,6 +2191,7 @@ t_stat cpuio_clr_inp (UNIT *uptr)
 {
 cpuio_inp = 0;
 cpuio_opc = 0;
+cpuio_dev = 0;
 cpuio_cnt = 0;
 if (uptr != NULL)
     sim_cancel (uptr);
@@ -2225,6 +2239,7 @@ DEVICE *dptr;
 if (cpuio_inp != 0) {                                   /* IO in progress? */
     cpuio_inp = 0;
     cpuio_opc = 0;
+    cpuio_dev = 0;
     cpuio_cnt = 0;
     for (i = 0; (dptr = sim_devices[i]) != NULL; i++) {
         if (((dptr->flags & DEV_DEFIO) != 0) && (dptr->reset != NULL))

I1620/i1620_defs.h

@@ -250,8 +250,9 @@ enum opcodes {
 #endif
 /* Function declarations */
 
-t_stat cpuio_set_inp (uint32 op, UNIT *uptr);
+t_stat cpuio_set_inp (uint32 op, uint32 dev, UNIT *uptr);
 t_stat cpuio_clr_inp (UNIT *uptr);
+const char *opc_lookup (uint32 op, uint32 qv, uint32 *fl);
 
 extern const int8 cdr_to_alp[128];
 extern const int8 alp_to_cdp[256];

I1620/i1620_error_matrix.txt

@@ -0,0 +1,29 @@
+Device  Error                   Action
+
+CDR     RN, RA invalid char     set RDCHK; if IOSTOP set, stop simulator with INVCHR
+        unattached              stop simulator with UNATT (CHANGED - used to set RDCHK too)
+        end of file             stop simulator witn NOCD (CHANGED - used to set RDCHK too)
+        file read error         set RDCHK; stop simulator with IOERR
+        input line too long     set RDCHK; stop simulator with IOERR
+
+CDP     WN,DN invalid digit     set WRCHK; if IOSTOP set, stop simulator with INVCHR
+        WA invalid char         set WRCHK; if IOSTOP set, stop simulator with INVCHR
+        unattached              stop simulator with UNATT (CHANGED - used to set WRCHK too)
+        file write error        set WRCHK; stop simulator with IOERR
+
+LPT     bad K control field     set PRCHK; if IOSTOP set, stop simulator with INVFNC
+        WN,DN invalid digit     set PRCHK and WRCHK; if IOSTOP set, stop simulator with INVFNC
+        WA invalid char         set PRCHK and WRCHK; if IOSTOP set, stop simulator with INVFNC
+        unattached              stop simulator with UNATT (CHANGED - used to set WRCHK too)
+        file write error        set PRCHK and WRCHK; stop simulator with IOERR
+
+PTR     RN, RA invalid char     set RDCHK but complete operation; if IOSTOP set at end, stop simulator with INVCHR
+        RN, RA parity error     set RDCHK but complete operation; if IOSTOP set at end, stop simulator with INVCHR
+        WN, DN invalid digit    set WRCHK; if IOSTOP set, stop simulator with INVCHR
+        WA invalid char         set WRCHK; if IOSTOP set, stop simulator with INVCHR
+        unattached              stop simulator with UNATT (CHANGED - used to set WRCHK too)
+        file write error        set WRCHK; stop simulator with IOERR
+
+TTY     RN, RA invalid char     ignored, echoed as beep/bell
+        WN, DN invalid digit    ignored, printed as :
+        WA invalid char         set WRCHK; if IOSTOP set, stop simulator with INVCHR

I1620/i1620_fp.c

@@ -186,7 +186,8 @@ uint8 d, l, z;
 z = 1;                                                  /* assume zero */
 for (l = 1; l <= FP_LMAX; l++) {                        /* scan to get length */
     d = M[ad] & DIGIT;                                  /* get mant digit */
-    if (d) z = 0;                                       /* non-zero? */
+    if (d)                                              /* non-zero? */
+        z = 0;
     if ((l != 1) && (M[ad] & FLAG)) {                   /* flag past first dig? */
         *lnt = l;                                       /* set returns */
         if (zro)

I1620/i1620_lp.c

@@ -1,6 +1,6 @@
 /* i1620_lp.c: IBM 1443 line printer simulator
 
-   Copyright (c) 2002-2015, Robert M. Supnik
+   Copyright (c) 2002-2017, Robert M. Supnik
 
    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the "Software"),
@@ -25,6 +25,8 @@
 
    lpt          1443 line printer
 
+   15-Jun-17    RMS     Fixed K constants and print-no-spacing (Tom McBride)
+                        Added option to emulate form feed with newlines
    31-Jan-15    TFM     Fixed various problems ... see comments in code
    10-Dec-13    RMS     Fixed DN wraparound (Bob Armstrong)
                         Fixed test on VFU 10 (Bob Armstrong)
@@ -37,10 +39,13 @@
 #include "i1620_defs.h"
 
 #define LPT_BSIZE       197                             /* buffer size */
+#define UNIT_V_FF       (UNIT_V_UF + 0)
+#define UNIT_FF         (1 << UNIT_V_FF)
 
-#define K_IMM           0x10                            /* control now */
+/* decoded print control */
+
+#define K_IMM           0x10                            /* before print */
 #define K_LIN           0x20                            /* spc lines */
-#define K_CH10          0x40                            /* chan 10 */
 #define K_LCNT          0x03                            /* line count */
 #define K_CHAN          0x0F                            /* channel */
 
@@ -59,8 +64,9 @@ t_stat lpt_svc (UNIT *uptr);
 t_stat lpt_reset (DEVICE *dptr);
 t_stat lpt_attach (UNIT *uptr, CONST char *cptr);
 void lpt_buf_init (void);
-t_stat lpt_num(uint32 pa, uint32 f1, t_bool dump);      /* tfm: length parameter removed, not needed */
+t_stat lpt_num(uint32 pa, uint32 f1, t_bool dump);
-t_stat lpt_print (void);
+t_stat lpt_print (uint32 flag);
+t_stat lpt_spcop (int32 ctrl);
 t_stat lpt_space (int32 lines, int32 lflag);
 
 #define CHP(ch,val)     ((val) & (1 << (ch)))
@@ -79,7 +85,7 @@ UNIT lpt_unit = {
 REG lpt_reg[] = {
     { BRDATAD (LBUF, lpt_buf, 8, 8, LPT_BSIZE + 1, "line buffer") },
     { DRDATAD (BPTR, lpt_bptr, 8, "buffer pointer") },
-    { HRDATAD (PCTL, lpt_savctrl, 8, "saved print control directive") },
+    { HRDATAD (PCTL, lpt_savctrl, 6, "saved print control directive") },
     { FLDATAD (PRCHK, ind[IN_PRCHK], 0, "print check indicator") },
     { FLDATAD (PRCH9, ind[IN_PRCH9], 0, "channel 9 indicator") },
     { FLDATAD (PRCH12, ind[IN_PRCH12], 0, "channel 12 indicator") },
@@ -91,8 +97,14 @@ REG lpt_reg[] = {
     { NULL }
     };
 
+MTAB lp_mod[] = {
+    { UNIT_FF, 0, "no form feeds", "NOFF", NULL },
+    { UNIT_FF, UNIT_FF, "form feeds", "FF", NULL }, 
+    { 0 }
+    };
+
 DEVICE lpt_dev = {
-    "LPT", &lpt_unit, lpt_reg, NULL,
+    "LPT", &lpt_unit, lpt_reg, lp_mod,
     1, 10, 31, 1, 8, 7,
     NULL, NULL, &lpt_reset,
     NULL, &lpt_attach, NULL
@@ -103,10 +115,10 @@ DEVICE lpt_dev = {
 /* Numeric (flag plus digit) to lineprinter (ASCII) */
 
 const int8 num_to_lpt[32] = {
- '0', '1', '2', '3', '4', '5', '6', '7',                /* tfm: All invalid char treated as errors */
+ '0', '1', '2', '3', '4', '5', '6', '7',                /* All invalid char treated as errors */
- '8', '9', '|', -1,  '@',  -1,  -1, 'G',                /* tfm: @, G only print on DN; else NB is blank */
+ '8', '9', '|', -1,  '@',  -1,  -1, 'G',                /* @, G only print on DN; else NB is blank */
  '-', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
- 'Q', 'R', 'W',  -1, '*',  -1,  -1, 'X'                 /* tfm: W, *, X only print on DN */
+ 'Q', 'R', 'W',  -1, '*',  -1,  -1, 'X'                 /* W, *, X only print on DN */
  };
 
 /* Alphameric (digit pair) to lineprinter (ASCII) */
@@ -146,6 +158,24 @@ const int8 alp_to_lpt[256] = {                          /* tfm: invalid codes 02
   -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1
  };
 
+/* K validation and translation table - entryies 80:FF always 0 */
+
+static const int8 lpt_ktbl[128] = {
+  0, 0, 0, 11, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,     /* 00 */
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,       /* 10 */
+  0, K_LIN|1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 20 */
+  0, 0, 0, K_IMM|11, K_IMM|12, 0, 0, 0, 0, 0,           /* 30 */
+         0, 0, 0, 0, 0, 0,
+  10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 0, 0, 0, 0, 0,      /* 40 */
+  0, K_IMM|K_LIN|1, K_IMM|K_LIN|2, K_IMM|K_LIN|3, 0,    /* 50 */
+         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, K_LIN|2, K_LIN|3, 0, 0, 0, 0, 0, 0,             /* 60 */
+         0, 0, 0, 0, 0, 0,
+  K_IMM|10, K_IMM|1, K_IMM|2, K_IMM|3, K_IMM|4,         /* 70 */
+         K_IMM|5, K_IMM|6, K_IMM|7, K_IMM|8, K_IMM|9,
+         0, 0, 0, 0, 0, 0,
+  };
+
 /* Line printer IO routine
  
    - Hard errors halt the system.
@@ -157,6 +187,7 @@ t_stat lpt (uint32 op, uint32 pa, uint32 f0, uint32 f1)
 {
 int8 lpc;
 uint8 z, d;
+int32 ctrl;
 t_stat r, sta;
 
 sta = SCPE_OK;
@@ -166,16 +197,24 @@ ind[IN_PRBSY] = 0;                                      /* printer free */
 switch (op) {                                           /* decode op */
 
     case OP_K:                                          /* control */
-        lpt_savctrl = (f0 << 4) | f1;                   /* form ctrl */
+        ctrl = lpt_ktbl[((f0 & 0x7) << 4) | (f1 & 0xF)]; /* xlate ctrl */
-        if (lpt_savctrl & K_IMM)                        /* immediate? */
+        if ((f0 > 7) || (ctrl == 0)) {                  /* invalid? */
-            return lpt_print ();
+            ind[IN_PRCHK] = 1;                          /* print chk */
-        break;
+            if (io_stop)                                /* set return status */
+                sta = STOP_INVFNC;
+            }
+        else {
+            if ((ctrl & K_IMM) != 0)                    /* immediate? */
+                return lpt_spcop (ctrl);                /* execute */
+            else lpt_savctrl = ctrl;                    /* otherwise, save */
+            }
+        return sta;
 
     case OP_DN:
-        return lpt_num (pa, f1, TRUE);                  /* dump numeric  (tfm: removed len parm ) */
+        return lpt_num (pa, f1, TRUE);                  /* dump numeric */
 
     case OP_WN:
-        return lpt_num (pa, f1, FALSE);                 /* write numeric (tfm: removed len parm ) */
+        return lpt_num (pa, f1, FALSE);                 /* write numeric */
 
     case OP_WA:
         for ( ; lpt_bptr < LPT_BSIZE; lpt_bptr++) {     /* only fill buf */
@@ -192,11 +231,9 @@ switch (op) {                                           /* decode op */
             lpt_buf[lpt_bptr] = lpc & 0x7F;             /* fill buffer */
             pa = ADDR_A (pa, 2);                        /* incr mem addr */
             }
-        if ((f1 & 1) == 0) {            ;               /* print now? */
+        r = lpt_print (f1);                             /* print line */
-            r = lpt_print ();                           /* print line */
         if (r != SCPE_OK)
             return r;
-            }
         return sta;
 
     default:                                            /* invalid function */
@@ -208,7 +245,7 @@ return SCPE_OK;
 
 /* Print numeric */
 
-t_stat lpt_num (uint32 pa, uint32 f1, t_bool dump)      /* tfm: removed len parm and reorganized code */
+t_stat lpt_num (uint32 pa, uint32 f1, t_bool dump)
 {
 uint8 d;
 int8 lpc;
@@ -232,57 +269,55 @@ for ( ; lpt_bptr < LPT_BSIZE; lpt_bptr++) {             /* only fill buf */
     lpt_buf[lpt_bptr] = lpc & 0x7F;                     /* put char into buffer (tfm: correct increment)*/
     PP (pa);                                            /* incr mem addr */
     }
-if ((f1 & 1) == 0) {                                    /* print now? */
+r = lpt_print (f1);                                     /* print line */
-    r = lpt_print ();                                   /* print line */
+if (r != SCPE_OK)
-    if (r != SCPE_OK)
     return r;
-    }
 return sta;
 }
 
-/* Print and space */
+/* Print and possibly space - any spacing operation is non-immediate */
 
-t_stat lpt_print (void)
+t_stat lpt_print (uint32 flag)
 {
-int32 i, chan, ctrl = lpt_savctrl;
+int32 i;
 
 if ((lpt_unit.flags & UNIT_ATT) == 0) {                 /* not attached? */
-    ind[IN_PRCHK] = ind[IN_WRCHK] = 1;                  /* wr, pri check */
+    ind[IN_PRCHK] = 1;                                  /* pri check */
     return SCPE_UNATT;
     }
 
-ind[IN_PRBSY] = 1;                                      /* print busy */
-sim_activate (&lpt_unit, lpt_unit.wait);                /* start timer */
-
 for (i = LPT_WIDTH; i <= LPT_BSIZE; i++)                /* clear unprintable */
     lpt_buf[i] = ' ';
 while ((lpt_bptr > 0) && (lpt_buf[lpt_bptr - 1] == ' '))
     lpt_buf[--lpt_bptr] = 0;                            /* trim buffer */
-if (lpt_bptr) {                                         /* any line? */
+if (lpt_bptr != 0) {                                    /* any line? */
     fputs (lpt_buf, lpt_unit.fileref);                  /* print */
+    if ((flag & 1) != 0)                                /* no space? */
+        fputc ('\r', lpt_unit.fileref);                 /* bare return */
     lpt_unit.pos = ftell (lpt_unit.fileref);            /* update pos */
     lpt_buf_init ();                                    /* reinit buf */
     if (ferror (lpt_unit.fileref)) {                    /* error? */
-        ind[IN_PRCHK] = ind[IN_WRCHK] = 1;              /* wr, pri check */
+        ind[IN_PRCHK] = 1;                              /* pri check */
         sim_perror ("LPT I/O error");
         clearerr (lpt_unit.fileref);
         return SCPE_IOERR;
         }
     }
+if ((flag & 1) == 0)                                    /* spacing? */
+    return lpt_spcop (lpt_savctrl);                     /* execute */
+return SCPE_OK;                                         /* done */
+}
 
-lpt_savctrl = 0x61;                                     /* reset ctrl */
+/* Space operation - direct (K) or deferred (WA, WN, DN) */
-if ((ctrl & K_LIN) == ((ctrl & K_IMM)? 0: K_LIN))       /* space lines? */
+
-    return lpt_space (ctrl & K_LCNT, FALSE);
+t_stat lpt_spcop (int32 ctrl)
-chan = lpt_savctrl & K_CHAN;                            /* basic chan */
+{
-if ((lpt_savctrl & K_CH10) == 0) {                      /* chan 10-12? */
+int32 chan, i;
-    if (chan == 0)
+
-        chan = 10;
+lpt_savctrl = K_LIN|1;                                  /* reset saved control */
-    else if (chan == 3)
+if ((ctrl & K_LIN) != 0)                                /* space lines? */
-        chan = 11;
+    return lpt_space (ctrl & K_LCNT, FALSE);            /* execute spacing op */
-    else if (chan == 4)
+chan = lpt_savctrl & K_CHAN;                            /* get chan */
-        chan = 12;
-    else chan = 0;
-    }
 if ((chan == 0) || (chan > 12))
     return STOP_INVFNC;
 for (i = 1; i < cct_lnt + 1; i++) {                     /* sweep thru cct */
@@ -304,7 +339,8 @@ t_stat lpt_space (int32 count, int32 sflag)
 int32 i;
 
 cct_ptr = (cct_ptr + count) % cct_lnt;                  /* adv cct, mod lnt */
-if (sflag && CHP (0, cct[cct_ptr]))                     /* skip, top of form? */
+if (sflag && CHP (0, cct[cct_ptr]) &&                   /* skip, top of form, */
+    ((lpt_unit.flags & UNIT_FF) != 0))                  /* and use form feeds? */
     fputs ("\n\f", lpt_unit.fileref);                   /* nl, ff */
 else {
     for (i = 0; i < count; i++)                         /* count lines */
@@ -319,6 +355,8 @@ if (ferror (lpt_unit.fileref)) {                        /* error? */
     clearerr (lpt_unit.fileref);
     return SCPE_IOERR;
     }
+ind[IN_PRBSY] = 1;                                      /* print busy */
+sim_activate (&lpt_unit, lpt_unit.wait);                /* start timer */
 return SCPE_OK;
 }
 
@@ -348,7 +386,7 @@ t_stat lpt_reset (DEVICE *dptr)
 {
 lpt_buf_init ();                                        /* clear buffer */
 cct_ptr = 0;                                            /* clear cct ptr */
-lpt_savctrl = 0x61;                                     /* clear cct action */
+lpt_savctrl = K_LIN|1;                                  /* reset cct action */
 ind[IN_PRCHK] = ind[IN_PRBSY] = 0;                      /* clear indicators */
 ind[IN_PRCH9] = ind[IN_PRCH12] = 0;
 return SCPE_OK;

I1620/i1620_pt.c

@@ -26,6 +26,7 @@
    ptr          1621 paper tape reader
    ptp          1624 paper tape punch
 
+   23-Jun-17    RMS     PTR/PTP errors does not set read check
    10-Jun-17    RMS     Fixed typo in PTP unit (Dave Wise)
    26-May-17    RMS     Added deferred IO
    25-May-17    RMS     Fixed treatment of X0C82 on RN (Tom McBride)
@@ -232,7 +233,7 @@ if ((op != OP_RN) && (op != OP_RA))                     /* RN & RA only */
 if ((ptr_unit.flags & UNIT_ATT) == 0)                   /* catch unattached */
     return SCPE_UNATT;
 ptr_mode = 0;
-cpuio_set_inp (op, &ptr_unit);
+cpuio_set_inp (op, IO_PTR, &ptr_unit);
 return SCPE_OK;
 }
 
@@ -245,7 +246,7 @@ if (op != OP_RA)                                        /* RA only */
 if ((ptr_unit.flags & UNIT_ATT) == 0)                   /* catch unattached */
     return SCPE_UNATT;
 ptr_mode = 1;
-cpuio_set_inp (op, &ptr_unit);
+cpuio_set_inp (op, IO_BTR, &ptr_unit);
 return SCPE_OK;
 }
 
@@ -343,7 +344,6 @@ int32 temp;
 
 do {
     if ((temp = getc (ptr_unit.fileref)) == EOF) {      /* read char */
-        ind[IN_RDCHK] = 1;                              /* err, rd chk */
         if (feof (ptr_unit.fileref)) {                  /* EOF? */
             sim_printf ("PTR end of file\n");
             clearerr (ptr_unit.fileref);
@@ -398,7 +398,7 @@ if ((op != OP_WN) && (op != OP_WA) && (op != OP_DN))
 if ((ptp_unit.flags & UNIT_ATT) == 0)                   /* catch unattached */
     return SCPE_UNATT;
 ptp_mode = 0;
-cpuio_set_inp (op, &ptp_unit);
+cpuio_set_inp (op, IO_PTP, &ptp_unit);
 return SCPE_OK;
 }
 
@@ -411,7 +411,7 @@ if (op != OP_WA)                                        /* WA only */
 if ((ptp_unit.flags & UNIT_ATT) == 0)                   /* catch unattached */
     return SCPE_UNATT;
 ptp_mode = 1;
-cpuio_set_inp (op, &ptp_unit);
+cpuio_set_inp (op, IO_BTP, &ptp_unit);
 return SCPE_OK;
 }
 
@@ -505,7 +505,6 @@ return SCPE_OK;
 t_stat ptp_write (uint32 c)
 {
 if (putc (c, ptp_unit.fileref) == EOF) {                /* write char */
-    ind[IN_WRCHK] = 1;                                  /* error? */
     sim_perror ("PTP I/O error");
     clearerr (ptp_unit.fileref);
     return SCPE_IOERR;

I1620/i1620_sys.c

@@ -303,6 +303,34 @@ if ((cpu_unit.flags & IF_IDX) && flg) {                 /* indexing? */
 return;
 }
 
+/* Look up an opcode
+
+   Inputs:
+        op      =       opcode (decimal)
+        qv      =       Q value (full 5 digits)
+    Outputs:
+        *opcst  =       pointer to opcode string
+                        (NULL if not found)
+        *fl     =       opcode flags (optional)
+*/
+
+const char *opc_lookup (uint32 op, uint32 qv, uint32 *fl)
+{
+uint32 i, opfl;
+
+for (i = 0; opcode[i].str != NULL; i++) {               /* find opcode */
+    opfl = opcode[i].opv & 0xFF0000;                    /* get flags */
+    if ((op == (opcode[i].opv & 0xFF)) &&               /* op match? */
+        ((qv == opcode[i].qv) ||                        /* q match or */
+        ((opfl != I_1E) && (opfl != I_0E)))) {          /* not needed? */
+            if (fl != NULL)
+                *fl = opfl;
+            return opcode[i].str;
+        }
+    }
+return NULL;
+}
+
 /* Symbolic decode
 
    Inputs:
@@ -323,6 +351,7 @@ t_stat fprint_sym (FILE *of, t_addr addr, t_value *val,
 {
 int32 pmp, qmp, i, c, d, any;
 uint32 op, qv, opfl;
+const char *opstr;
 
 if (uptr == NULL)
     uptr = &cpu_unit;
@@ -383,14 +412,9 @@ for (i = qv = pmp = qmp = 0; i < ADDR_LEN; i++) {       /* test addr */
     }
 if ((val[0] | val[1]) & FLAG)                           /* flags force */
     pmp = qmp = 1;
-for (i = 0; opcode[i].str != NULL; i++) {               /* find opcode */
+opstr = opc_lookup (op, qv, &opfl);                     /* find opcode */
-    opfl = opcode[i].opv & 0xFF0000;
+
-    if ((op == (opcode[i].opv & 0xFF)) &&
+if (opstr == NULL) {                                    /* invalid opcode */
-        ((qv == opcode[i].qv) ||
-        ((opfl != I_1E) && (opfl != I_0E))))
-        break;
-    }
-if (opcode[i].str == NULL) {                            /* invalid opcode */
     if ((sw & SIM_SW_STOP) != 0) {                      /* stop message? */
         fprintf (of, "%02d", op);                       /* print numeric opcode */
         return -(INST_LEN - 1);                         /* report success */
@@ -400,7 +424,7 @@ if (opcode[i].str == NULL) {                            /* invalid opcode */
 if (I_GETQP (opfl) == I_M_QNP)                          /* Q no print? */
     qmp = 0;
 
-fprintf (of, "%-4s", opcode[i].str);                      /* print opcode */
+fprintf (of, ((sw & SIM_SW_STOP)? "%s": "%-4s"), opstr);/* print opcode */
 if (I_GETPP (opfl) == I_M_PP)                           /* P required? */
     fprint_addr (of, ' ', &val[I_P], I_M_QX);
 else if ((I_GETPP (opfl) == I_M_PCP) && (pmp || qmp))   /* P opt & needed? */

I1620/i1620_tty.c

@@ -136,7 +136,7 @@ DEVICE tty_dev = {
 /* The following constant is a list of valid 1620 numeric characters 
    that can be entered from the keyboard. They are the digits 0-9, 
    record mark(|), numeric blank(@) and group mark(}). All others
-   are cosidered invalid. When entering data, these characters may
+   are considered invalid. When entering data, these characters may
    all be preceeded by tilde(~) or accent(`) to indicate that the
    following character should be entered into storage with a flag.
 
@@ -285,7 +285,7 @@ switch (op) {                                           /* case on op */
     case OP_WN:
     case OP_DN:
     case OP_WA:
-        cpuio_set_inp (op, &tty_unit[UTTO]);            /* set IO in progress */
+        cpuio_set_inp (op, IO_TTY, &tty_unit[UTTO]);    /* set IO in progress */
         break;
 
     case OP_RN:
@@ -293,7 +293,7 @@ switch (op) {                                           /* case on op */
         tti_unlock = 1;                                 /* unlock keyboard */
         tti_flag = 0;                                   /* init flag */
         tto_write ('>');                                /* prompt user */
-        cpuio_set_inp (op, NULL);                       /* set IO in progress */
+        cpuio_set_inp (op, IO_TTY, NULL);               /* set IO in progress */
         break;
 
     default:                                            /* invalid function */
@@ -316,7 +316,7 @@ if ((temp = sim_poll_kbd ()) < SCPE_KFLAG)              /* no char or error? */
     return temp;
 if (tti_unlock == 0)                                    /* expecting input? */
     return SCPE_OK;                                     /* no, ignore */
-raw = (int8) temp;
+raw = (int8) (temp & 0x7F);
 
 if (raw == '\r') {                                      /* return? */
     tto_write (raw);                                    /* echo */