TX-0/tx0_sys.c - emulators/simh - Rivoreo Source Code Repositories

 /*************************************************************************
  *                                                                       *
  * $Id: tx0_sys.c 2061 2009-02-24 07:05:58Z hharte $                     *
  *                                                                       *
  * Copyright (c) 2009-2012 Howard M. Harte.                              *
  * Based on pdp1_sys.c, Copyright (c) 1993-2007, 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"), to deal in the Software without restriction, including   *
  * without limitation the rights to use, copy, modify, merge, publish,   *
  * distribute, sublicense, and/or sell copies of the Software, and to    *
  * permit persons to whom the Software is furnished to do so, subject to *
  * the following conditions:                                             *
  *                                                                       *
  * The above copyright notice and this permission notice shall be        *
  * included in all copies or substantial portions of the Software.       *
  *                                                                       *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       *
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    *
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND                 *
  * NONINFRINGEMENT. IN NO EVENT SHALL HOWARD M. HARTE BE LIABLE FOR ANY  *
  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  *
  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     *
  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                *
  *                                                                       *
  * Except as contained in this notice, the name of Howard M. Harte shall *
  * not be used in advertising or otherwise to promote the sale, use or   *
  * other dealings in this Software without prior written authorization   *
  * of Howard M. Harte.                                                   *
  *                                                                       *
  * Module Description:                                                   *
  *     TX-0 simulator interface                                          *
  *                                                                       *
  * Environment:                                                          *
  *     User mode only                                                    *
  *                                                                       *
  *************************************************************************/

 #include "tx0_defs.h"
 #include <ctype.h>

 extern DEVICE cpu_dev;
 extern DEVICE petr_dev;
 extern DEVICE tto_dev;
 extern DEVICE tti_dev;
 extern DEVICE ptp_dev;
 #ifdef USE_DISPLAY
 extern DEVICE dpy_dev;
 #endif /* USE_DISPLAY */

 #ifdef USE_FPC
 extern DEVICE fpc_dev;
 #endif /* USE_FPC */
 extern UNIT cpu_unit;
 extern REG cpu_reg[];
 extern int32 M[];
 extern int32 PC;
 extern int32 ascii_to_flexo[], flexo_to_ascii[];
 extern int32 sc_map[];

 /* SCP data structures and interface routines

    sim_name             simulator name string
    sim_PC               pointer to saved PC register descriptor
    sim_emax             number of words for examine
    sim_devices          array of pointers to simulated devices
    sim_stop_messages    array of pointers to stop messages
    sim_load             binary loader
 */

 char sim_name[] = "TX-0";

 REG *sim_PC = &cpu_reg[0];

 int32 sim_emax = 1;

 DEVICE *sim_devices[] = {
     &cpu_dev,
     &petr_dev,
     &tti_dev,
     &tto_dev,
     &ptp_dev,
 #ifdef USE_DISPLAY
     &dpy_dev,
 #endif/* USE_DISPLAY */
 #ifdef USE_FPC
     &fpc_dev,
 #endif /* USE_FPC */
     NULL
     };

 const char *sim_stop_messages[] = {
     "Unknown error",
     "Undefined instruction",
     "HALT instruction",
     "Breakpoint",
     "Nested XCT's",
     "Nested indirect addresses",
     "Infinite I/O wait state",
     "DECtape off reel"
      };

 int32 tx0_getw (FILE *inf)
 {
 int32 i, tmp, word;

 word = 0;
 for (i = 0; i < 3;) {
     if ((tmp = getc (inf)) == EOF) return -1;
     if (tmp & 0200) {
         word = (word << 6) | (tmp & 077);
         i++;
         }
     }
 return word;
 }

 /* Symbol tables */
 typedef struct {
     int32 opr;
     const char *mnemonic;
     const char *desc;
 } OPMAP;

 typedef struct {
     const char *mnemonic;
     const char *desc;
 } INSTMAP;

 const INSTMAP instmap[] = {
 /* Store Class */
     { "sto", "Store AC" },
     { "stx", "Store AC, Indexed" },
     { "sxa", "Store XR in Address" },
     { "ado", "Add One" },
     { "slr", "Store LR" },
     { "slx", "Store LR, Indexed" },
     { "stz", "Store Zero" },
     { "[!sto-nop]", "NOP" },

 /* Add Class */
     { "add", "Add" },
     { "adx", "Add, Indexed" },
     { "ldx", "Load XR" },
     { "aux", "Augment XR" },
     { "llr", "Load LR" },
     { "llx", "Load LR, Indexed" },
     { "lda", "Load AC" },
     { "lax", "Load AC, Indexed" },

 /* Transfer Class */
     { "trn", "Transfer Negative" },
     { "trz", "Transfer +/- Zero" },
     { "tsx", "Transfer and set Index" },
     { "tix", "Transfer and Index" },
     { "tra", "Transfer" },
     { "trx", "Transfer Indexed" },
     { "tlv", "Transfer on external Level" },
     { "[!tra-nop]", "NOP" }
 };

 const OPMAP opmap [] = {
     { 0600000, "opr", "No operation" },
     { 0600001, "xro", "Clear XR to +0" },
     { 0600003, "lxr", "Place LR in XR" },
     { 0600012, "cry", "Carry the contents of AC according to bits of LR" },
     { 0600022, "lpd", "Logical exclusive or of AC is placed in AC (partial add)" },
     { 0600032, "lad", "Add LR to AC" },
     { 0600040, "com", "Compliment the AC" },
     { 0600072, "lcd", "Contents of LR minus those of AC are placed in AC" },
     { 0600130, "xad", "Add index register to accumulator" },
     { 0600170, "xcd", "Contents of XR minus those of AC are placed in AC" },
     { 0600200, "lro", "Clear LR to +0" },
     { 0600300, "xlr", "Place XR in LR" },
     { 0600303, "ixl", "Interchange XR and LR" },
     { 0600400, "shr", "Shift accumulator right one place, bit 0 remains unchanged" },
     { 0600600, "cyr", "Cycle AC right one place" },
     { 0603000, "pen", "Contents of light pen and light cannon flip-flops replace contents of AC bits 0 and 1. The flip-flops are cleared." },
     { 0604000, "bsr", "Backspace tape unit by one record" },
     { 0604004, "rtb", "Read tape binary (odd parity)" },
     { 0604004, "rds", "Select tape unit for reading a record" },
     { 0604010, "rew", "Rewind tape unit" },
     { 0604014, "wtb", "Write tape binary (odd parity)" },
     { 0604014, "wrs", "Select tape unit for writing a record" },
     { 0604024, "rtd", "Read tape decimal (even parity)" },
     { 0604034, "wtd", "Write tape decimal (even parity)" },
     { 0607000, "cpf", "The program flag is cleared" },
     { 0620000, "cpy", "Transmit information between the live register and selected input-output unit" },
     { 0622000, "dis", "Display point on CRT corresponding to contents of AC" },
     { 0624000, "prt", "Print one on-line flexo character from bits 2, 5, etc." },
     { 0624600, "pnt", "PRT, then cycle AC right once to set up another character" },
     { 0625000, "typ", "Read one character from on-line flexowriter into LR bits 12-17" },
     { 0626600, "p6h", "Punch one line of paper tape; 6 holes from bits 2, 5, etc. of AC then cycle right once." },
     { 0627600, "p7h", "Same as p6h, but punch 7th hole" },
     { 0630000, "hlt", "Stops computer" },
     { 0631000, "cll", "Clear left half of AC to zero" },
     { 0632000, "clr", "Clear right half of AC" },
     { 0632022, "---", "CLR+PAD+LMB" },
     { 0640001, "axr", "Place AC contents in XR" },
     { 0640021, "axo", "AXR, then set AC to +0" },
     { 0640030, "cyl", "Cycle AC left one place" },
     { 0640031, "alx", "AXR, then cycle AC left once" },
     { 0640040, "amz", "Add minus zero to AC" },
     { 0640061, "axc", "AXR, then set AC to -0" },
     { 0640200, "alr", "Place accumulator contents in live register" },
     { 0640201, "---", "ALR+MBX, Place accumulator contents in live register, Transfer MBR to XR." },
     { 0640203, "rax", "Place LR in XR, then place AC in LR" },
     { 0640205, "orl", "Logical or of AC and LR is placed in LR" },
     { 0640207, "anl", "Logical and of AC and LR is placed in LR" },
     { 0640220, "alo", "ALR, then set AC to +0" },
     { 0640230, "all", "ALR, then cycle left once" },
     { 0640231, "---", "AMB+MBL+PAD+CRY+MBX" },
     { 0640232, "iad", "Interchange and add AC contents are placed in the LR and the previous contents of the LR ar added to AC" },
     { 0640260, "alc", "ALR, then set AC to -0" },
     { 0640601, "arx", "AXR, then cycle AC right once" },
     { 0647000, "spf", "Place AC in program flag register" },
     { 0662020, "dso", "DIS, then clear AC" },
     { 0664020, "pno", "PRT, then clear AC" },
     { 0664060, "pnc", "PRT, then clear AC to -0" },
     { 0666020, "p6o", "p6h then clear AC" },
     { 0667020, "p7o", "p7h then clear AC" },
     { 0700000, "cla", "Clear entire AC to +0" },
     { 0700001, "cax", "Clear AC and XR to +0" },
     { 0700012, "lal", "Place LR in AC cycled left once" },
     { 0700022, "lac", "Place LR in AC" },
     { 0700040, "clc", "Clear and complement: set AC to -0" },
     { 0700062, "lcc", "Place complement of LR in AC" },
     { 0700072, "laz", "Add LR to minus zero in AC" },
     { 0700110, "xal", "XAC, then cycle AC left once" },
     { 0700120, "xac", "Place index register in accumulator" },
     { 0700160, "xcc", "Place complement of XR in accumulator" },
     { 0700200, "cal", "Clear AC and LR to +0" },
     { 0700322, "rxe", "Place LR in AC, then place XR in LR" },
     { 0700622, "lar", "Place LR in AC cycled right once" },
     { 0701000, "tac", "Contents of test accumulator are placed in AC" },
     { 0702020, "tbr", "Contents of test buffer register are placed in AC" },
     { 0703000, "---", "Clear AC and read light pen" },
     { 0706020, "rpf", "The program flag register is placed in AC" },
     { 0721000, "rlc", "Read one line paper tape into AC bits 0, 3, etc." },
     { 0721600, "rlr", "rlc, then cycle AC right once" },
     { 0723000, "r3c", "Read three lines of paper tape" },
     { 0723032, "---", "R3C+LMB+PAD+CRY" },
     { 0726000, "p6a", "Clear AC and punch a line of blank tape" },
     { 0740025, "ora", "Logical or of AC and LR is placed in AC" },
     { 0740027, "ana", "Logical and of AC and LR is placed in AC" },
     { 0740207, "anc", "ANL, then clear AC" },
     { 0740205, "oro", "ORL, then clear AC" },
     { 0740222, "ial", "Interchange AC and LR" },
     { 0763232, "---", "AMB+CLA+R3L+MBL+LMB+PAD+CRY" },
     { 0766020, "p6b", "Punch a line of blank tape, but save AC" },
     { 0000000, NULL, NULL }
 };

 /* Symbolic decode

    Inputs:
         *of     =       output stream
         addr    =       current PC
         *val    =       pointer to values
         *uptr   =       pointer to unit
         sw      =       switches
    Outputs:
         return  =       status code
 */

 #define FMTASC(x) ((x) < 040)? "<%03o>": "%c", (x)
 #define SIXTOASC(x) flexo_to_ascii[x]
 #define ASCTOSIX(x) (ascii_to_flexo[x] & 077)

 extern int32 cpu_get_mode (void);
 extern t_stat fprint_sym_orig (FILE *of, t_addr addr, t_value *val,
     UNIT *uptr, int32 sw);


 t_stat fprint_sym (FILE *of, t_addr addr, t_value *val,
     UNIT *uptr, int32 sw)
 {
 int32 i, inst, op;

 if(!cpu_get_mode()) {
     return fprint_sym_orig (of, addr, val, uptr, sw);
 }


 inst = val[0];
 if (sw & SWMASK ('A')) {                                /* ASCII? */
     if (inst > 0377) return SCPE_ARG;
     fprintf (of, FMTASC (inst & 0177));
     return SCPE_OK;
     }
 if (sw & SWMASK ('F')) {
     fputc (flexo_to_ascii[inst & 077], of);
     return SCPE_OK;
     }
 if (sw & SWMASK ('C')) {                                /* character? */
     fprintf (of, "%c", SIXTOASC ((inst >> 12) & 077));
     fprintf (of, "%c", SIXTOASC ((inst >> 6) & 077));
     fprintf (of, "%c", SIXTOASC (inst & 077));
     return SCPE_OK;
     }
 if (!(sw & SWMASK ('M'))) return SCPE_ARG;

 /* Instruction decode */

     op = (inst >> 13) & 037;

     if ((op & 030) != 030) /* sto, add, trn (not an opr) */
     {
         fprintf (of, "%s %05o (%s)", instmap[op].mnemonic, inst & 017777, instmap[op].desc);
     } else { /* opr */
         for(i=0;opmap[i].opr != 0;i++) {
             if(inst == opmap[i].opr) {
                 fprintf (of, "opr %s (%s)", opmap[i].mnemonic, opmap[i].desc);
             }
         }
     }
 return SCPE_OK;
 }

 /* Get 18b signed number

    Inputs:
         *cptr   =       pointer to input string
         *sign   =       pointer to sign
         *status =       pointer to error status
    Outputs:
         val     =       output value
 */

 t_value get_sint (char *cptr, int32 *sign, t_stat *status)
 {
 *sign = 1;
 if (*cptr == '+') {
     *sign = 0;
     cptr++;
     }
 else if (*cptr == '-') {
     *sign = -1;
     cptr++;
     }
 return get_uint (cptr, 8, DMASK, status);
 }

 /* Symbolic input

    Inputs:
         *cptr   =       pointer to input string
         addr    =       current PC
         uptr    =       pointer to unit
         *val    =       pointer to output values
         sw      =       switches
    Outputs:
         status  =       error status
 */
 t_stat parse_sym (CONST char *cptr, t_addr addr, UNIT *uptr, t_value *val, int32 sw)
 {
 #if 0
     int32 cflag, d, i, j, k, sign;
 t_stat r;
 static int32 sc_enc[10] = { 0, 01, 03, 07, 017, 037, 077, 0177, 0377, 0777 };
 char gbuf[CBUFSIZE];

 cflag = (uptr == NULL) || (uptr == &cpu_unit);
 while (isspace (*cptr)) cptr++;
 for (i = 1; (i < 3) && (cptr[i] != 0); i++)
     if (cptr[i] == 0) for (j = i + 1; j <= 3; j++) cptr[j] = 0;
 if ((sw & SWMASK ('A')) || ((*cptr == '\'') && cptr++)) { /* ASCII char? */
     if (cptr[0] == 0) return SCPE_ARG;                  /* must have 1 char */
     val[0] = (t_value) cptr[0];
     return SCPE_OK;
     }
 if ((sw & SWMASK ('C')) || ((*cptr == '"') && cptr++)) { /* sixbit string? */
     if (cptr[0] == 0) return SCPE_ARG;                  /* must have 1 char */
     val[0] = ((ASCTOSIX (cptr[0]) & 077) << 12) |
              ((ASCTOSIX (cptr[1]) & 077) << 6) |
               (ASCTOSIX (cptr[2]) & 077);
     return SCPE_OK;
     }

 cptr = get_glyph (cptr, gbuf, 0);                       /* get opcode */
 for (i = 0; (opcode[i] != NULL) && (strcmp (opcode[i], gbuf) != 0) ; i++) ;
 if (opcode[i] == NULL) return SCPE_ARG;
 val[0] = opc_val[i] & DMASK;                            /* get value */
 j = (opc_val[i] >> I_V_FL) & I_M_FL;                    /* get class */

 switch (j) {                                            /* case on class */

     case I_V_LAW:                                       /* LAW */
         cflag = 0;                                      /* fall through */
     case I_V_MRF: case I_V_MRI:                         /* mem ref */
         cptr = get_glyph (cptr, gbuf, 0);               /* get next field */
         if ((j != I_V_MRI) && strcmp (gbuf, "I") == 0) { /* indirect? */
             val[0] = val[0] | IA;
             cptr = get_glyph (cptr, gbuf, 0);
             }
         d = get_uint (gbuf, 8, AMASK, &r);
         if (r != SCPE_OK) return SCPE_ARG;
         if (d <= DAMASK) val[0] = val[0] | d;
         else if (cflag && (((addr ^ d) & EPCMASK) == 0))
                 val[0] = val[0] | (d & DAMASK);
         else return SCPE_ARG;
         break;

     case I_V_SHF:                                       /* shift */
         cptr = get_glyph (cptr, gbuf, 0);
         d = get_uint (gbuf, 10, 9, &r);
         if (r != SCPE_OK) return SCPE_ARG;
         val[0] = val[0] | sc_enc[d];
         break;

     case I_V_NPN: case I_V_IOT:
     case I_V_OPR: case I_V_SKP: case I_V_SPC:
         for (cptr = get_glyph (cptr, gbuf, 0); gbuf[0] != 0;
             cptr = get_glyph (cptr, gbuf, 0)) {
             for (i = 0; (opcode[i] != NULL) &&
                         (strcmp (opcode[i], gbuf) != 0); i++) ;
             if (opcode[i] != NULL) {
                 k = opc_val[i] & DMASK;
                 if ((k != IA) && (((k ^ val[0]) & 0760000) != 0))
                     return SCPE_ARG;
                 val[0] = val[0] | k;
                 }
             else {
                 d = get_sint (gbuf, &sign, &r);
                 if (r != SCPE_OK) return SCPE_ARG;
                 if (sign == 0) val[0] = val[0] + d;
                 else if (sign < 0) val[0] = val[0] - d;
                 else val[0] = val[0] | d;
                 }
             }
         break;
         }                                               /* end case */
 if (*cptr != 0) return SCPE_ARG;                        /* junk at end? */
 #endif
 return SCPE_ARG;
 }
	/*************************************************************************
	* *
	* $Id: tx0_sys.c 2061 2009-02-24 07:05:58Z hharte $ *
	* *
	* Copyright (c) 2009-2012 Howard M. Harte. *
	* Based on pdp1_sys.c, Copyright (c) 1993-2007, 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"), to deal in the Software without restriction, including *
	* without limitation the rights to use, copy, modify, merge, publish, *
	* distribute, sublicense, and/or sell copies of the Software, and to *
	* permit persons to whom the Software is furnished to do so, subject to *
	* the following conditions: *
	* *
	* The above copyright notice and this permission notice shall be *
	* included in all copies or substantial portions of the Software. *
	* *
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, *
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND *
	* NONINFRINGEMENT. IN NO EVENT SHALL HOWARD M. HARTE BE LIABLE FOR ANY *
	* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, *
	* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE *
	* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
	* *
	* Except as contained in this notice, the name of Howard M. Harte shall *
	* not be used in advertising or otherwise to promote the sale, use or *
	* other dealings in this Software without prior written authorization *
	* of Howard M. Harte. *
	* *
	* Module Description: *
	* TX-0 simulator interface *
	* *
	* Environment: *
	* User mode only *
	* *
	*************************************************************************/

	#include "tx0_defs.h"
	#include <ctype.h>

	extern DEVICE cpu_dev;
	extern DEVICE petr_dev;
	extern DEVICE tto_dev;
	extern DEVICE tti_dev;
	extern DEVICE ptp_dev;
	#ifdef USE_DISPLAY
	extern DEVICE dpy_dev;
	#endif /* USE_DISPLAY */

	#ifdef USE_FPC
	extern DEVICE fpc_dev;
	#endif /* USE_FPC */
	extern UNIT cpu_unit;
	extern REG cpu_reg[];
	extern int32 M[];
	extern int32 PC;
	extern int32 ascii_to_flexo[], flexo_to_ascii[];
	extern int32 sc_map[];

	/* SCP data structures and interface routines

	sim_name simulator name string
	sim_PC pointer to saved PC register descriptor
	sim_emax number of words for examine
	sim_devices array of pointers to simulated devices
	sim_stop_messages array of pointers to stop messages
	sim_load binary loader
	*/

	char sim_name[] = "TX-0";

	REG *sim_PC = &cpu_reg[0];

	int32 sim_emax = 1;

	DEVICE *sim_devices[] = {
	&cpu_dev,
	&petr_dev,
	&tti_dev,
	&tto_dev,
	&ptp_dev,
	#ifdef USE_DISPLAY
	&dpy_dev,
	#endif/* USE_DISPLAY */
	#ifdef USE_FPC
	&fpc_dev,
	#endif /* USE_FPC */
	NULL
	};

	const char *sim_stop_messages[] = {
	"Unknown error",
	"Undefined instruction",
	"HALT instruction",
	"Breakpoint",
	"Nested XCT's",
	"Nested indirect addresses",
	"Infinite I/O wait state",
	"DECtape off reel"
	};

	int32 tx0_getw (FILE *inf)
	{
	int32 i, tmp, word;

	word = 0;
	for (i = 0; i < 3;) {
	if ((tmp = getc (inf)) == EOF) return -1;
	if (tmp & 0200) {
	word = (word << 6) \| (tmp & 077);
	i++;
	}
	}
	return word;
	}

	/* Symbol tables */
	typedef struct {
	int32 opr;
	const char *mnemonic;
	const char *desc;
	} OPMAP;

	typedef struct {
	const char *mnemonic;
	const char *desc;
	} INSTMAP;

	const INSTMAP instmap[] = {
	/* Store Class */
	{ "sto", "Store AC" },
	{ "stx", "Store AC, Indexed" },
	{ "sxa", "Store XR in Address" },
	{ "ado", "Add One" },
	{ "slr", "Store LR" },
	{ "slx", "Store LR, Indexed" },
	{ "stz", "Store Zero" },
	{ "[!sto-nop]", "NOP" },

	/* Add Class */
	{ "add", "Add" },
	{ "adx", "Add, Indexed" },
	{ "ldx", "Load XR" },
	{ "aux", "Augment XR" },
	{ "llr", "Load LR" },
	{ "llx", "Load LR, Indexed" },
	{ "lda", "Load AC" },
	{ "lax", "Load AC, Indexed" },

	/* Transfer Class */
	{ "trn", "Transfer Negative" },
	{ "trz", "Transfer +/- Zero" },
	{ "tsx", "Transfer and set Index" },
	{ "tix", "Transfer and Index" },
	{ "tra", "Transfer" },
	{ "trx", "Transfer Indexed" },
	{ "tlv", "Transfer on external Level" },
	{ "[!tra-nop]", "NOP" }
	};

	const OPMAP opmap [] = {
	{ 0600000, "opr", "No operation" },
	{ 0600001, "xro", "Clear XR to +0" },
	{ 0600003, "lxr", "Place LR in XR" },
	{ 0600012, "cry", "Carry the contents of AC according to bits of LR" },
	{ 0600022, "lpd", "Logical exclusive or of AC is placed in AC (partial add)" },
	{ 0600032, "lad", "Add LR to AC" },
	{ 0600040, "com", "Compliment the AC" },
	{ 0600072, "lcd", "Contents of LR minus those of AC are placed in AC" },
	{ 0600130, "xad", "Add index register to accumulator" },
	{ 0600170, "xcd", "Contents of XR minus those of AC are placed in AC" },
	{ 0600200, "lro", "Clear LR to +0" },
	{ 0600300, "xlr", "Place XR in LR" },
	{ 0600303, "ixl", "Interchange XR and LR" },
	{ 0600400, "shr", "Shift accumulator right one place, bit 0 remains unchanged" },
	{ 0600600, "cyr", "Cycle AC right one place" },
	{ 0603000, "pen", "Contents of light pen and light cannon flip-flops replace contents of AC bits 0 and 1. The flip-flops are cleared." },
	{ 0604000, "bsr", "Backspace tape unit by one record" },
	{ 0604004, "rtb", "Read tape binary (odd parity)" },
	{ 0604004, "rds", "Select tape unit for reading a record" },
	{ 0604010, "rew", "Rewind tape unit" },
	{ 0604014, "wtb", "Write tape binary (odd parity)" },
	{ 0604014, "wrs", "Select tape unit for writing a record" },
	{ 0604024, "rtd", "Read tape decimal (even parity)" },
	{ 0604034, "wtd", "Write tape decimal (even parity)" },
	{ 0607000, "cpf", "The program flag is cleared" },
	{ 0620000, "cpy", "Transmit information between the live register and selected input-output unit" },
	{ 0622000, "dis", "Display point on CRT corresponding to contents of AC" },
	{ 0624000, "prt", "Print one on-line flexo character from bits 2, 5, etc." },
	{ 0624600, "pnt", "PRT, then cycle AC right once to set up another character" },
	{ 0625000, "typ", "Read one character from on-line flexowriter into LR bits 12-17" },
	{ 0626600, "p6h", "Punch one line of paper tape; 6 holes from bits 2, 5, etc. of AC then cycle right once." },
	{ 0627600, "p7h", "Same as p6h, but punch 7th hole" },
	{ 0630000, "hlt", "Stops computer" },
	{ 0631000, "cll", "Clear left half of AC to zero" },
	{ 0632000, "clr", "Clear right half of AC" },
	{ 0632022, "---", "CLR+PAD+LMB" },
	{ 0640001, "axr", "Place AC contents in XR" },
	{ 0640021, "axo", "AXR, then set AC to +0" },
	{ 0640030, "cyl", "Cycle AC left one place" },
	{ 0640031, "alx", "AXR, then cycle AC left once" },
	{ 0640040, "amz", "Add minus zero to AC" },
	{ 0640061, "axc", "AXR, then set AC to -0" },
	{ 0640200, "alr", "Place accumulator contents in live register" },
	{ 0640201, "---", "ALR+MBX, Place accumulator contents in live register, Transfer MBR to XR." },
	{ 0640203, "rax", "Place LR in XR, then place AC in LR" },
	{ 0640205, "orl", "Logical or of AC and LR is placed in LR" },
	{ 0640207, "anl", "Logical and of AC and LR is placed in LR" },
	{ 0640220, "alo", "ALR, then set AC to +0" },
	{ 0640230, "all", "ALR, then cycle left once" },
	{ 0640231, "---", "AMB+MBL+PAD+CRY+MBX" },
	{ 0640232, "iad", "Interchange and add AC contents are placed in the LR and the previous contents of the LR ar added to AC" },
	{ 0640260, "alc", "ALR, then set AC to -0" },
	{ 0640601, "arx", "AXR, then cycle AC right once" },
	{ 0647000, "spf", "Place AC in program flag register" },
	{ 0662020, "dso", "DIS, then clear AC" },
	{ 0664020, "pno", "PRT, then clear AC" },
	{ 0664060, "pnc", "PRT, then clear AC to -0" },
	{ 0666020, "p6o", "p6h then clear AC" },
	{ 0667020, "p7o", "p7h then clear AC" },
	{ 0700000, "cla", "Clear entire AC to +0" },
	{ 0700001, "cax", "Clear AC and XR to +0" },
	{ 0700012, "lal", "Place LR in AC cycled left once" },
	{ 0700022, "lac", "Place LR in AC" },
	{ 0700040, "clc", "Clear and complement: set AC to -0" },
	{ 0700062, "lcc", "Place complement of LR in AC" },
	{ 0700072, "laz", "Add LR to minus zero in AC" },
	{ 0700110, "xal", "XAC, then cycle AC left once" },
	{ 0700120, "xac", "Place index register in accumulator" },
	{ 0700160, "xcc", "Place complement of XR in accumulator" },
	{ 0700200, "cal", "Clear AC and LR to +0" },
	{ 0700322, "rxe", "Place LR in AC, then place XR in LR" },
	{ 0700622, "lar", "Place LR in AC cycled right once" },
	{ 0701000, "tac", "Contents of test accumulator are placed in AC" },
	{ 0702020, "tbr", "Contents of test buffer register are placed in AC" },
	{ 0703000, "---", "Clear AC and read light pen" },
	{ 0706020, "rpf", "The program flag register is placed in AC" },
	{ 0721000, "rlc", "Read one line paper tape into AC bits 0, 3, etc." },
	{ 0721600, "rlr", "rlc, then cycle AC right once" },
	{ 0723000, "r3c", "Read three lines of paper tape" },
	{ 0723032, "---", "R3C+LMB+PAD+CRY" },
	{ 0726000, "p6a", "Clear AC and punch a line of blank tape" },
	{ 0740025, "ora", "Logical or of AC and LR is placed in AC" },
	{ 0740027, "ana", "Logical and of AC and LR is placed in AC" },
	{ 0740207, "anc", "ANL, then clear AC" },
	{ 0740205, "oro", "ORL, then clear AC" },
	{ 0740222, "ial", "Interchange AC and LR" },
	{ 0763232, "---", "AMB+CLA+R3L+MBL+LMB+PAD+CRY" },
	{ 0766020, "p6b", "Punch a line of blank tape, but save AC" },
	{ 0000000, NULL, NULL }
	};

	/* Symbolic decode

	Inputs:
	*of = output stream
	addr = current PC
	*val = pointer to values
	*uptr = pointer to unit
	sw = switches
	Outputs:
	return = status code
	*/

	#define FMTASC(x) ((x) < 040)? "<%03o>": "%c", (x)
	#define SIXTOASC(x) flexo_to_ascii[x]
	#define ASCTOSIX(x) (ascii_to_flexo[x] & 077)

	extern int32 cpu_get_mode (void);
	extern t_stat fprint_sym_orig (FILE of, t_addr addr, t_value val,
	UNIT *uptr, int32 sw);


	t_stat fprint_sym (FILE of, t_addr addr, t_value val,
	UNIT *uptr, int32 sw)
	{
	int32 i, inst, op;

	if(!cpu_get_mode()) {
	return fprint_sym_orig (of, addr, val, uptr, sw);
	}


	inst = val[0];
	if (sw & SWMASK ('A')) { /* ASCII? */
	if (inst > 0377) return SCPE_ARG;
	fprintf (of, FMTASC (inst & 0177));
	return SCPE_OK;
	}
	if (sw & SWMASK ('F')) {
	fputc (flexo_to_ascii[inst & 077], of);
	return SCPE_OK;
	}
	if (sw & SWMASK ('C')) { /* character? */
	fprintf (of, "%c", SIXTOASC ((inst >> 12) & 077));
	fprintf (of, "%c", SIXTOASC ((inst >> 6) & 077));
	fprintf (of, "%c", SIXTOASC (inst & 077));
	return SCPE_OK;
	}
	if (!(sw & SWMASK ('M'))) return SCPE_ARG;

	/* Instruction decode */

	op = (inst >> 13) & 037;

	if ((op & 030) != 030) /* sto, add, trn (not an opr) */
	{
	fprintf (of, "%s %05o (%s)", instmap[op].mnemonic, inst & 017777, instmap[op].desc);
	} else { /* opr */
	for(i=0;opmap[i].opr != 0;i++) {
	if(inst == opmap[i].opr) {
	fprintf (of, "opr %s (%s)", opmap[i].mnemonic, opmap[i].desc);
	}
	}
	}
	return SCPE_OK;
	}

	/* Get 18b signed number

	Inputs:
	*cptr = pointer to input string
	*sign = pointer to sign
	*status = pointer to error status
	Outputs:
	val = output value
	*/

	t_value get_sint (char cptr, int32 sign, t_stat *status)
	{
	*sign = 1;
	if (*cptr == '+') {
	*sign = 0;
	cptr++;
	}
	else if (*cptr == '-') {
	*sign = -1;
	cptr++;
	}
	return get_uint (cptr, 8, DMASK, status);
	}

	/* Symbolic input

	Inputs:
	*cptr = pointer to input string
	addr = current PC
	uptr = pointer to unit
	*val = pointer to output values
	sw = switches
	Outputs:
	status = error status
	*/
	t_stat parse_sym (CONST char cptr, t_addr addr, UNIT uptr, t_value *val, int32 sw)
	{
	#if 0
	int32 cflag, d, i, j, k, sign;
	t_stat r;
	static int32 sc_enc[10] = { 0, 01, 03, 07, 017, 037, 077, 0177, 0377, 0777 };
	char gbuf[CBUFSIZE];

	cflag = (uptr == NULL) \|\| (uptr == &cpu_unit);
	while (isspace (*cptr)) cptr++;
	for (i = 1; (i < 3) && (cptr[i] != 0); i++)
	if (cptr[i] == 0) for (j = i + 1; j <= 3; j++) cptr[j] = 0;
	if ((sw & SWMASK ('A')) \|\| ((cptr == '\'') && cptr++)) { / ASCII char? */
	if (cptr[0] == 0) return SCPE_ARG; /* must have 1 char */
	val[0] = (t_value) cptr[0];
	return SCPE_OK;
	}
	if ((sw & SWMASK ('C')) \|\| ((cptr == '"') && cptr++)) { / sixbit string? */
	if (cptr[0] == 0) return SCPE_ARG; /* must have 1 char */
	val[0] = ((ASCTOSIX (cptr[0]) & 077) << 12) \|
	((ASCTOSIX (cptr[1]) & 077) << 6) \|
	(ASCTOSIX (cptr[2]) & 077);
	return SCPE_OK;
	}

	cptr = get_glyph (cptr, gbuf, 0); /* get opcode */
	for (i = 0; (opcode[i] != NULL) && (strcmp (opcode[i], gbuf) != 0) ; i++) ;
	if (opcode[i] == NULL) return SCPE_ARG;
	val[0] = opc_val[i] & DMASK; /* get value */
	j = (opc_val[i] >> I_V_FL) & I_M_FL; /* get class */

	switch (j) { /* case on class */

	case I_V_LAW: /* LAW */
	cflag = 0; /* fall through */
	case I_V_MRF: case I_V_MRI: /* mem ref */
	cptr = get_glyph (cptr, gbuf, 0); /* get next field */
	if ((j != I_V_MRI) && strcmp (gbuf, "I") == 0) { /* indirect? */
	val[0] = val[0] \| IA;
	cptr = get_glyph (cptr, gbuf, 0);
	}
	d = get_uint (gbuf, 8, AMASK, &r);
	if (r != SCPE_OK) return SCPE_ARG;
	if (d <= DAMASK) val[0] = val[0] \| d;
	else if (cflag && (((addr ^ d) & EPCMASK) == 0))
	val[0] = val[0] \| (d & DAMASK);
	else return SCPE_ARG;
	break;

	case I_V_SHF: /* shift */
	cptr = get_glyph (cptr, gbuf, 0);
	d = get_uint (gbuf, 10, 9, &r);
	if (r != SCPE_OK) return SCPE_ARG;
	val[0] = val[0] \| sc_enc[d];
	break;

	case I_V_NPN: case I_V_IOT:
	case I_V_OPR: case I_V_SKP: case I_V_SPC:
	for (cptr = get_glyph (cptr, gbuf, 0); gbuf[0] != 0;
	cptr = get_glyph (cptr, gbuf, 0)) {
	for (i = 0; (opcode[i] != NULL) &&
	(strcmp (opcode[i], gbuf) != 0); i++) ;
	if (opcode[i] != NULL) {
	k = opc_val[i] & DMASK;
	if ((k != IA) && (((k ^ val[0]) & 0760000) != 0))
	return SCPE_ARG;
	val[0] = val[0] \| k;
	}
	else {
	d = get_sint (gbuf, &sign, &r);
	if (r != SCPE_OK) return SCPE_ARG;
	if (sign == 0) val[0] = val[0] + d;
	else if (sign < 0) val[0] = val[0] - d;
	else val[0] = val[0] \| d;
	}
	}
	break;
	} /* end case */
	if (cptr != 0) return SCPE_ARG; / junk at end? */
	#endif
	return SCPE_ARG;
	}