HP2100: Most recent updates from Dave Bryan

HP2100/hp2100_baci.c

@@ -156,7 +156,6 @@
 #include <ctype.h>
 
 #include "hp2100_defs.h"
-#include "sim_sock.h"
 #include "sim_tmxr.h"
 
 

HP2100/hp2100_bugfixes.txt

@@ -1,6 +1,6 @@
                        HP 2100 SIMULATOR BUG FIX WRITEUPS
                        ==================================
-                             Last update: 2012-12-28
+                             Last update: 2014-12-19
 
 
   1. PROBLEM:  Booting from magnetic tape reports "HALT instruction, P: 77756
@@ -6391,3 +6391,355 @@
      name during a power-on reset.
 
      STATUS:  Fixed in version 4.0-0.
+
+
+
+251. PROBLEM:  Constants required for exdep_cmd and brk_cmd aren't in scp.h.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The scp.h header file exports the exdep_cmd and brk_cmd
+     functions, but the constants that must be passed in the "flag" parameters
+     for proper operation are not present.  The run_cmd function also requires
+     constants for the "flag" parameter, but these are present.
+
+     CAUSE:  Oversight.
+
+     RESOLUTION:  Move the EX_D, EX_E, EX_I, SSH_ST, SSH_CL, and SSH_SH
+     constants from scp.c to scp.h.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+252. PROBLEM:  Stop calls VM-provided address printer for PC without REG_VMAD.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  For a simulator stop, sim_vm_fprint_addr (if defined) is
+     called to print the value of the program counter, regardless of whether or
+     not the register was defined with REG_VMAD.  However, displaying the PC
+     value with "examine" calls sim_vm_fprint_addr only if the REG_VMAD flag is
+     present.  The displayed value of the PC should be the same in both cases.
+
+     CAUSE:  The call to sim_vm_fprint_addr in fprint_stopped_gen is not
+     conditional on the PC register having the REG_VMAD flag.
+
+     RESOLUTION:  Modify "fprint_stopped_gen" (scp.c) to require REG_VMAD before
+     calling the VM-specific address printer for the program counter value.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+253. PROBLEM:  Cannot show radix, etc. for a device that has no modifiers.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The default data radix for a device may be set with the SET
+     <dev> OCT|DEC|HEX command.  However, if the device does not have a modifier
+     table, SHOW <dev> RADIX is rejected with "No settable parameters".
+
+     The same problem occurs for SHOW <dev> DEBUG and SHOW <dev> NAMES.  For a
+     device that provides debug printouts, SHOW <dev> MOD will list "DEBUG,
+     NODEBUG" among the modifiers, and the SHOW <dev> DEBUG command will display
+     the current debug status.  However, if the device does not contain a
+     modifier table, SHOW <dev> MOD and SHOW <dev> DEBUG will report "No
+     settable parameters", even though SET <dev> DEBUG is accepted and works as
+     expected.  For such a device, SHOW MOD will show "DEBUG, NODEBUG" as
+     acceptable modifiers.
+
+     CAUSE:  The "show_cmd_fi" routine checks for a modifier table and returns
+     an error without checking for global actions.
+
+     RESOLUTION:  Modify "show_cmd_fi" (scp.c) to continue to process global
+     actions if the modifier table is not defined.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+254. PROBLEM:  SET and SHOW responses for invalid entry are inconsistent.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  Entering SET <dev> <mod> where <mod> is not defined in the
+     device's modifier table displays "Non-existent parameter."  Entering SHOW
+     with the same parameters displays "Invalid argument."
+
+     Similarly, entering SET <dev> DEBUG for a device that does not have
+     debugging capability displays "Command not allowed."  Entering SHOW with
+     the same parameters displays nothing.
+
+     In both cases, the messages displayed should be the same for the same
+     error.
+
+     CAUSE:  Oversight.
+
+     RESOLUTION:  Modify "show_cmd_fi" (scp.c) to return the same status codes
+     as "set_cmd" does.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+255. ENHANCEMENT:  Add a "-N" (new file) option to the SET CONSOLE LOG and SET
+     CONSOLE DEBUG commands.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  These commands normally append to their respective log files.
+     If the user wants to recreate the log file instead, it must be deleted
+     first with OS-specific commands.  Adding a "-N" option to perform the
+     delete removes commands dependent on a specific OS.
+
+     RESOLUTION:  Modify "sim_set_logon" and "sim_set_debon" (sim_console.c) to
+     check for a "-N" option and to open for writing instead of appending if
+     detected.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+256. ENHANCEMENT: Add tape runaway support to the simulator tape library.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The ANSI specifications for NRZI, PE, and GCR tape recording
+     mandate a maximum length of 25 feet for erase gaps.  Currently, an erase
+     gap of any length is ignored when reading or spacing.  To allow detection
+     of non-compliant tape images, the simulator tape library is enhanced to
+     halt positioning and return tape runaway status if a gap of 25 feet or more
+     is encountered.
+
+     Runaway detection is enabled by calling the tape library to set the tape
+     density in bits per inch.  If this call is not made, erase gaps present in
+     a tape image are effectively ignored.  Also, with the addition of a
+     separate "set density" call, it is no longer necessary to supply the
+     density when writing erase gaps.
+
+     RESOLUTION:  Modify "sim_tape_rdlntf" and "sim_tape_rdlntr" (sim_tape.c) to
+     detect tape runaway, and add a new MTSE_RUNAWAY status to sim_tape.h.  Add
+     new "sim_tape_set_dens" and "sim_tape_show_dens" functions to set and show
+     the bits per inch for a unit, respectively, and eliminate the "bpi"
+     parameter to "sim_tape_wrgap" in preference to using the density
+     established by a previous "sim_tape_set_dens" call.  Add named constants
+     to "sim_tape.h" that specify the density.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+257. ENHANCEMENT:  Improve performance when reading or spacing over erase gaps.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  Performance when reading or spacing over erase gaps is poor,
+     especially in the reverse direction.  Currently, each 4-byte gap marker is
+     read individually, and in the reverse direction, each read is preceded by a
+     seek to move the file pointer backward.  This combination causes stream
+     cache invalidation and a physical disc access for each gap marker.  As a
+     single gap consists of over 1000 markers, performance is far worse than if
+     a gap was read as a block.
+
+     RESOLUTION:  Modify "sim_tape_rdlntf" and "sim_tape_rdlntr" (sim_tape.c) to
+     buffer reads of gap markers.  Using a 128-element buffer, performance
+     improves about thirty-fold.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+258. PROBLEM:  Writing an end-of-medium positions the tape image after the mark.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The "sim_tape_wreom" simulator tape library function writes
+     an end-of-medium marker on the tape image.  The intent is to erase the
+     remainder of the tape.  The "SIMH Magtape Representation and Handling"
+     document states that the tape position is not updated by this function.
+     However, the function leaves the tape positioned after the marker.
+
+     A subsequent read would stop at the EOM marker.  However, writing a new
+     marker over that one would then allow reading of the data following the EOM
+     that supposedly had been erased by the original "sim_tape_wreom" call.
+
+     CAUSE:  The tape position is updated by the internal "sim_tape_wrdata" call
+     that is used to write the EOM marker, but it is not reset afterward by the
+     function.
+
+     RESOLUTION:  Modify "sim_tape_wreom" (sim_tape.c) to reset the tape
+     position to point at the EOM marker before returning.  This prevents
+     reading past an EOM marker, and a subsequent write will overwrite the
+     marker rather than embed it between data records.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+259. PROBLEM:  Reading through an erase gap in reverse may return EOM status.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  A reverse read or spacing operation through an erase gap may
+     return end-of-medium status.  Reading or spacing forward through the same
+     gap works properly.
+
+     CAUSE:  Writing an erase gap over existing records may produce a gap that
+     is longer than requested.  This occurs when truncating the last record to
+     be overlaid by the gap would leave a record that is shorter than the
+     minimum size allowed (eight bytes for the length words plus two bytes for
+     the data).  In this case, the gap is lengthened to overlay the entire
+     record.  If the new gap size is not evenly divisible by four, a half-gap is
+     metadata marker of value 0xFFFF added to the beginning of the gap.
+
+     If a gap that begins with a half-gap marker is written immediately after
+     a previous gap, the "seam" between gaps will contain the bytes FE FF FF FF
+     ( FF FF ) FE FF FF FF....  Reading forward across this seam will yield a
+     metadata value of 0xFFFEFFFF, which is recognized and handled by seeking
+     two bytes back to resynchronize reading.  However, reading in reverse will
+     yield the value 0xFFFFFFFF, which is interpreted as end-of-medium.
+
+     RESOLUTION:  Modify "sim_tape_rdlntr" (sim_tape.c) to recognize 0xFFFFFFFF
+     as a half-gap marker and resynchronize in response.  End of medium cannot
+     occur when reading in reverse, as it is impossible to position the tape
+     image beyond an EOM marker.  Therefore, any 0xFFFFFFFF value encountered
+     must be a half-gap "seam" originating as above.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+260. PROBLEM:  sim_tape_wrgap fails when format is changed from SIMH format.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The HP 2100 magnetic tape simulator supports erase gaps and
+     calls sim_tape_wrgap when commanded to write a gap.  However, if a tape
+     format other than SIMH format is selected, the call fails with MTSE_FMT.
+
+     CAUSE:  Erase gaps are not supported in formats other than SIMH, but the
+     call should not fail.  Instead, the call should be a "no-operation" if the
+     underlying format does not support gaps.
+
+     RESOLUTION:  Modify "sim_tape_wrgap" (sim_tape.c) to return MTSE_OK with no
+     action performed if a tape format other than SIMH is selected.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+261. PROBLEM:  The magnetic tape format of an attached unit may be changed.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The magnetic tape library supports several tape image
+     formats.  The format to use may be specified either by an "ATTACH -F"
+     command or by a "SET <unit> FORMAT" command.  The latter calls the
+     "sim_tape_set_fmt" function, which allows the format of a file currently
+     attached to be changed.  However, the format is an intrinsic property of
+     the tape image file, so changing it once the file has been attached makes
+     no sense.
+
+     CAUSE:  Oversight.
+
+     RESOLUTION:  Modify "sim_tape_set_fmt" (sim_tape.c) to return an error
+     (SCPE_ALATT, "Unit already attached") if the unit is attached.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+262. ENHANCEMENT:  Add CRCC and LRCC support to the HP 2100 MS simulation.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The HP 2100 MS device simulates the HP 7970 B/E magnetic tape
+     drives.  The 7970B uses NRZI format, and its associated controller supports
+     returning the cyclic redundancy check character and longitudinal redundancy
+     check character (CRCC and LRCC) to the CPU.  Typically, these are used only
+     by the controller diagnostic, but support is easy to add.
+
+     RESOLUTION:  Modify "hp2100_ms.c" to add a function that calculates CRCC
+     and LRCC for reads and writes, and call that function when the CPU requests
+     that the controller deliver the values.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+263. ENHANCEMENT:  Allow the VM to print simulator stop message information in
+     lieu of, or in addition to, the default message.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  The current implementation of "run_cmd" in scp.c calls
+     "fprint_stopped_gen" (via "fprint_stopped") to print the message associated
+     with the "sim_instr" return status.  Messages associated with VM stops must
+     be provided to the SCP via the "sim_stop_messages" array.
+
+     "fprint_stopped_gen" prints the status message in a rigid format: the
+     message string, a comma, the program counter register name, a colon, the
+     current PC value, and the instruction at that address in symbolic format.
+     For example:
+
+       HALT instruction, P: 24713 (LDA 1)
+
+     Only the message string is under the control of the VM.  If additional
+     information is needed, it can only be added before the first comma.
+
+     The HP2100 simulator does this for halt instructions, which contain device
+     select code and flag hold/clear bit fields that, in practice, are used to
+     communicate to the operator the significance of the particular halt
+     encountered, rather than to affect the device interface:
+
+       HALT instruction 102077, P: 24713 (LDA 1)
+
+     To implement this, the simulator must define the message as a variable and
+     then copy the formatted octal value into the buffer at the appropriate
+     location before returning from "sim_instr".
+
+     However, if the VM wants to display a different register value, e.g.:
+
+       Self test #13 complete, STAT: 000020
+
+     ...this cannot be done without also displaying the program counter, which
+     may be irrelevant for the given stop condition.
+
+     RESOLUTION:  Modify "fprint_stopped_gen" (scp.c) to check a VM-specific
+     simulation stop printer pointer ("sim_vm_fprint_stopped") that is
+     initialized to NULL and can be overridden by the VM, and, if overridden,
+     call it after printing the message string and before printing the program
+     counter.  If the VM printer returns TRUE, print the comma and the program
+     counter as before. If the VM routine returns FALSE, print just the
+     terminating newline.
+
+     STATUS:  Fixed in version 4.0-0.
+
+
+
+264. ENHANCEMENT:  Indicate that "examine" is being called for a simulator stop.
+
+     VERSION:  3.9-0
+
+     OBSERVATION:  As part of the simulator stop message, the fprint_stopped_gen
+     routine prints the instruction pointed to by the program counter.  In
+     addition to the "M" (mnemonic) switch, it passes the SIM_SW_STOP flag to
+     the fprint_sym routine to indicate that it is being called for a simulator
+     stop.  This allows the VM-defined routine to take any action specifically
+     appropriate to the stop.
+
+     To get the instruction value, fprint_stopped_gen calls the CPU's "examine"
+     routine and passes the program counter value as the address.  However,
+     interpretation of addresses may differ, depending on context.  For example,
+     a given address may be relative to a code, data, or stack space pointer.
+     To attempt to address this, the "examine" call includes the "V" (virtual)
+     switch.  However, "virtual" (and the associated "-v" command line switch)
+     may have a different meaning assigned by a given VM.  What is needed is an
+     unequivocal indication that a machine instruction value is being retrieved.
+
+     RESOLUTION:  Modify "fprint_stopped_gen" (scp.c) to pass SIM_SW_STOP to
+     "examine" as well as "fprint_sym", so that these routines have unambiguous
+     indications that they are being called in the context of a simulator stop.
+
+     STATUS:  Fixed in version 4.0-0.

HP2100/hp2100_cpu.c

@@ -30,6 +30,7 @@
    DCPC1,DCPC2  12897B dual channel port controller
 
    18-Mar-13    JDB     Removed redundant extern declarations
+   05-Feb-13    JDB     HLT instruction handler now relies on sim_vm_fprint_stopped
    09-May-12    JDB     Separated assignments from conditional expressions
    13-Jan-12    JDB     Minor speedup in "is_mapped"
                         Added casts to cpu_mod, dmasio, dmapio, cpu_reset, dma_reset
@@ -563,7 +564,6 @@ uint16 dms_map[MAP_NUM * MAP_LNT] = { 0 };              /* dms maps */
 
 /* External data */
 
-extern char halt_msg [];                                /* halt message */
 extern DIB clk_dib;                                     /* CLK DIB for idle check */
 extern const BOOT_ROM ptr_rom, dq_rom, ms_rom, ds_rom;  /* boot ROMs for cpu_boot routine */
 
@@ -1987,9 +1987,7 @@ else if (sop == soMIX)                                  /* MIA/B instruction? */
     ABREG [ab] = ABREG [ab] | iodata;                   /* merge returned data */
 
 else if (sop == soHLT) {                                /* HLT instruction? */
-    const int32 len = strlen (halt_msg);                /* find end msg */
+    return STOP_HALT;                                   /* return halt status */
-    sprintf (&halt_msg[len - 6], "%06o", ir);           /* add the halt */
-    return STOP_HALT;
     }
 
 if (iostat == SCPE_OK)                                  /* normal status? */
@@ -3465,6 +3463,7 @@ if (M == NULL) {                                        /* initial call after st
         cpu_set_ldr (NULL, FALSE, NULL, NULL);          /* disable loader (was enabled) */
         SR = 0;                                         /* clear S */
         sim_vm_post = &hp_post_cmd;                     /* set cmd post proc */
+        sim_vm_fprint_stopped = &hp_fprint_stopped;     /* set sim stop printer */
         sim_brk_types = ALL_BKPTS;                      /* register allowed breakpoint types */
         }
     }
@@ -3579,7 +3578,8 @@ return;
 /* VM command post-processor
 
    Update T register to contents of memory addressed by M register
-   if M register has changed. */
+   if M register has changed.
+*/
 
 void hp_post_cmd (t_bool from_scp)
 {

HP2100/hp2100_cpu1.c

@@ -1,6 +1,6 @@
 /* hp2100_cpu1.c: HP 2100/1000 EAU simulator and UIG dispatcher
 
-   Copyright (c) 2005-2012, Robert M. Supnik
+   Copyright (c) 2005-2014, 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 +25,7 @@
 
    CPU1         Extended arithmetic and optional microcode dispatchers
 
+   05-Apr-14    JDB     Corrected typo in comments for cpu_ops
    09-May-12    JDB     Separated assignments from conditional expressions
    11-Sep-08    JDB     Moved microcode function prototypes to hp2100_cpu1.h
    05-Sep-08    JDB     Moved option-present tests to UIG dispatchers
@@ -666,7 +667,7 @@ return;
                                                            ...
                                                         I  DEC 0
 
-     OP_DAB  Double integer constant in A/B registers      DLD J    Value of J
+     OP_JAB  Double integer constant in A/B registers      DLD J    Value of J
                                                           [inst]
                                                            ...
                                                         J  DEC 0,0

HP2100/hp2100_defs.h

@@ -1,6 +1,6 @@
 /* hp2100_defs.h: HP 2100 simulator definitions
 
-   Copyright (c) 1993-2013, Robert M. Supnik
+   Copyright (c) 1993-2014, 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"),
@@ -23,6 +23,8 @@
    be used in advertising or otherwise to promote the sale, use or other dealings
    in this Software without prior written authorization from Robert M Supnik.
 
+   15-Dec-14    JDB     Added "-Wunused-const-variable" to the suppression pragmas
+   05-Feb-13    JDB     Added declaration for hp_fprint_stopped
    18-Mar-13    JDB     Added "-Wdangling-else" to the suppression pragmas
                         Removed redundant extern declarations
    14-Mar-13    MP      Changed guard macro name to avoid reserved namespace
@@ -85,6 +87,7 @@
 #pragma GCC diagnostic ignored "-Wlogical-op-parentheses"
 #pragma GCC diagnostic ignored "-Wbitwise-op-parentheses"
 #pragma GCC diagnostic ignored "-Wdangling-else"
+#pragma GCC diagnostic ignored "-Wunused-const-variable"
 #endif
 
 
@@ -469,6 +472,7 @@ extern t_stat      hp_setsc   (UNIT *uptr, int32 val, char *cptr, void *desc);
 extern t_stat      hp_showsc  (FILE *st, UNIT *uptr, int32 val, void *desc);
 extern t_stat      hp_setdev  (UNIT *uptr, int32 val, char *cptr, void *desc);
 extern t_stat      hp_showdev (FILE *st, UNIT *uptr, int32 val, void *desc);
+extern t_bool      hp_fprint_stopped (FILE *st, t_stat reason);
 
 /* Device-specific functions */
 

HP2100/hp2100_diag.txt

@@ -1,6 +1,6 @@
                       SIMH/HP 21XX DIAGNOSTICS PERFORMANCE
                       ====================================
-                             Last update: 2012-03-30
+                             Last update: 2014-12-18
 
 
 The HP 24396 diagnostic suite has been run against the SIMH HP 21xx simulation.
@@ -2481,7 +2481,7 @@ CONFIGURATION:  sim> detach MSC0
 
                 HALT instruction 102074
 
-                sim> deposit S 000217
+                sim> deposit S 000017
                 sim> reset
                 sim> go
 
@@ -2605,10 +2605,9 @@ TEST REPORT:    7970-13181 DIAG.
 
 TEST RESULT:    Partially passed.
 
-TEST NOTES:     Test 23 verifies the LRCC and CRCC values obtained from the
+TEST NOTES:     Test 23 performs a reverse record read to verify the CRCC and
-                interface.  These features are not simulated.  (Setting bit 7 of
+                LRCC values obtained from the record.  This feature is not
-                the S register during configuration eliminates most LRCC/CRCC
+                simulated.
-                checks but does not inhibit test 23.)
 
                 If test 34 is selected manually, E065 WRITE ERROR will occur.
                 This is due to the implementation of the tape simulation

HP2100/hp2100_mpx.c

@@ -142,7 +142,6 @@
 #include <ctype.h>
 
 #include "hp2100_defs.h"
-#include "sim_sock.h"
 #include "sim_tmxr.h"
 
 

HP2100/hp2100_mux.c

@@ -137,7 +137,6 @@
 #include <ctype.h>
 
 #include "hp2100_defs.h"
-#include "sim_sock.h"
 #include "sim_tmxr.h"
 
 

HP2100/hp2100_sys.c

@@ -23,6 +23,7 @@
    used in advertising or otherwise to promote the sale, use or other dealings
    in this Software without prior written authorization from Robert M Supnik.
 
+   05-Feb-13    JDB     Added hp_fprint_stopped to handle HLT instruction message
    18-Mar-13    JDB     Moved CPU state variable declarations to hp2100_cpu.h
    09-May-12    JDB     Quieted warnings for assignments in conditional expressions
    10-Feb-12    JDB     Deprecated DEVNO in favor of SC
@@ -94,8 +95,6 @@ extern DEVICE da_dev, dc_dev;
 
 char sim_name[] = "HP 2100";
 
-char halt_msg[] = "HALT instruction xxxxxx";
-
 REG *sim_PC = &cpu_reg[0];
 
 int32 sim_emax = 3;
@@ -129,7 +128,7 @@ const char *sim_stop_messages[] = {
     "Unknown error",
     "Unimplemented instruction",
     "Non-existent I/O device",
-    halt_msg,
+    "HALT instruction",
     "Breakpoint",
     "Indirect address loop",
     "Indirect address interrupt (should not happen!)",
@@ -138,6 +137,40 @@ const char *sim_stop_messages[] = {
     "Device/unit powered off"
     };
 
+
+/* Print additional information for simulator stops.
+
+   The HP 21xx/1000 halt instruction ("HLT") opcode includes select code and
+   device flag hold/clear bit fields.  In practice, these are not used to affect
+   the device interface; rather, they communicate to the operator the
+   significance of the particular halt encountered.
+
+   Under simulation, the halt opcode must be communicated to the user as part of
+   the stop message.  To so do, we define a sim_vm_fprint_stopped handler that
+   is called for all VM stops.  When called for a STOP_HALT, the halt message
+   has been printed, and we add the opcode value in the T register before
+   returning TRUE, so that SCP will add the program counter value.  For example:
+
+     HALT instruction 102077, P: 00101 (NOP)
+
+   Reasons other than STOP_HALT need no additional information.
+
+   Implementation notes:
+
+    1. The octal halt instruction will always be of the form 10x0xx.  We take
+       advantage of this to request 19 bits printed with leading spaces.  This
+       adds a leading space to separate the value from the message.
+*/
+
+t_bool hp_fprint_stopped (FILE *st, t_stat reason)
+{
+if (reason == STOP_HALT)
+    fprint_val (st, TR, 8, 19, PV_RSPC);
+
+return TRUE;
+}
+
+
 /* Binary loader
 
    The binary loader consists of blocks preceded and trailed by zero frames.