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/* pdp8_sys.c: PDP-8 simulator interface
Copyright (c) 1993-2005, 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
ROBERT M SUPNIK 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 Robert M Supnik shall not 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.
17-Oct-03 RMS Added TSC8-75, TD8E support, DECtape off reel message
25-Apr-03 RMS Revised for extended file support
30-Dec-01 RMS Revised for new TTX
26-Nov-01 RMS Added RL8A support
17-Sep-01 RMS Removed multiconsole support
16-Sep-01 RMS Added TSS/8 packed char support, added KL8A support
27-May-01 RMS Added multiconsole support
18-Mar-01 RMS Added DF32 support
14-Mar-01 RMS Added extension detection of RIM binary tapes
15-Feb-01 RMS Added DECtape support
30-Oct-00 RMS Added support for examine to file
27-Oct-98 RMS V2.4 load interface
10-Apr-98 RMS Added RIM loader support
17-Feb-97 RMS Fixed bug in handling of bin loader fields
*/
#include "pdp8_defs.h"
#include <ctype.h>
extern DEVICE cpu_dev;
extern UNIT cpu_unit;
extern DEVICE tsc_dev;
extern DEVICE ptr_dev, ptp_dev;
extern DEVICE tti_dev, tto_dev;
extern DEVICE clk_dev, lpt_dev;
extern DEVICE rk_dev, rl_dev;
extern DEVICE rx_dev;
extern DEVICE df_dev, rf_dev;
extern DEVICE dt_dev, td_dev;
extern DEVICE mt_dev;
extern DEVICE ttix_dev, ttox_dev;
extern REG cpu_reg[];
extern uint16 M[];
extern int32 sim_switches;
/* SCP data structures and interface routines
sim_name simulator name string
sim_PC pointer to saved PC register descriptor
sim_emax maximum number of words for examine/deposit
sim_devices array of pointers to simulated devices
sim_consoles array of pointers to consoles (if more than one)
sim_stop_messages array of pointers to stop messages
sim_load binary loader
*/
char sim_name[] = "PDP-8";
REG *sim_PC = &cpu_reg[0];
int32 sim_emax = 4;
DEVICE *sim_devices[] = {
&cpu_dev,
&tsc_dev,
&ptr_dev,
&ptp_dev,
&tti_dev,
&tto_dev,
&ttix_dev,
&ttox_dev,
&clk_dev,
&lpt_dev,
&rk_dev,
&rl_dev,
&rx_dev,
&df_dev,
&rf_dev,
&dt_dev,
&td_dev,
&mt_dev,
NULL
};
const char *sim_stop_messages[] = {
"Unknown error",
"Unimplemented instruction",
"HALT instruction",
"Breakpoint",
"Non-standard device number",
"DECtape off reel"
};
/* Binary loader
Two loader formats are supported: RIM loader (-r) and BIN (-b) loader.
RIM loader format consists of alternating pairs of addresses and 12-bit
words. It can only operate in field 0 and is not checksummed.
BIN loader format consists of a string of 12-bit words (made up from
7-bit characters) between leader and trailer (200). The last word on
tape is the checksum. A word with the "link" bit set is a new origin;
a character > 0200 indicates a change of field.
*/
t_stat sim_load (FILE *fileref, char *cptr, char *fnam, int flag)
{
int32 rubout, word, low, high, csum, newf, state, i;
uint32 origin, field;
if ((*cptr != 0) || (flag != 0)) return SCPE_ARG;
rubout = state = field = newf = origin = csum = 0;
if ((sim_switches & SWMASK ('R')) || /* RIM format? */
(match_ext (fnam, "RIM") && !(sim_switches & SWMASK ('B')))) {
while ((i = getc (fileref)) != EOF) {
switch (state) {
case 0: /* leader */
if ((i != 0) && (i < 0200)) state = 1;
high = i;
break;
case 1: /* low byte */
word = (high << 6) | i; /* form word */
if (word > 07777) origin = word & 07777;
else M[origin] = word;
state = 2;
break;
case 2: /* high byte */
if (i >= 0200) return SCPE_OK; /* end of tape? */
high = i; /* save high */
state = 1;
break;
} /* end switch */
} /* end while */
} /* end if */
else {
while ((i = getc (fileref)) != EOF) { /* BIN format */
if (rubout) {
rubout = 0;
continue;
}
if (i == 0377) {
rubout = 1;
continue;
}
if (i > 0200) {
newf = (i & 070) << 9;
continue;
}
switch (state) {
case 0: /* leader */
if ((i != 0) && (i != 0200)) state = 1;
high = i; /* save as high */
break;
case 1: /* low byte */
low = i;
state = 2;
break;
case 2: /* high with test */
word = (high << 6) | low;
if (i == 0200) { /* end of tape? */
if ((csum - word) & 07777) return SCPE_CSUM;
return SCPE_OK;
}
csum = csum + low + high;
if (word >= 010000) origin = word & 07777;
else {
if ((field | origin) >= MEMSIZE)
return SCPE_NXM;
M[field | origin] = word & 07777;
origin = (origin + 1) & 07777;
}
field = newf;
high = i;
state = 1;
break;
} /* end switch */
} /* end while */
} /* end else */
return SCPE_FMT; /* eof? error */
}
/* Symbol tables */
#define I_V_FL 18 /* flag start */
#define I_M_FL 07 /* flag mask */
#define I_V_NPN 0 /* no operand */
#define I_V_FLD 1 /* field change */
#define I_V_MRF 2 /* mem ref */
#define I_V_IOT 3 /* general IOT */
#define I_V_OP1 4 /* operate 1 */
#define I_V_OP2 5 /* operate 2 */
#define I_V_OP3 6 /* operate 3 */
#define I_NPN (I_V_NPN << I_V_FL)
#define I_FLD (I_V_FLD << I_V_FL)
#define I_MRF (I_V_MRF << I_V_FL)
#define I_IOT (I_V_IOT << I_V_FL)
#define I_OP1 (I_V_OP1 << I_V_FL)
#define I_OP2 (I_V_OP2 << I_V_FL)
#define I_OP3 (I_V_OP3 << I_V_FL)
static const int32 masks[] = {
07777, 07707, 07000, 07000,
07416, 07571, 017457
};
static const char *opcode[] = {
"SKON", "ION", "IOF", "SRQ",
"GTF", "RTF", "SGT", "CAF",
"RPE", "RSF", "RRB", "RFC", "RFC RRB",
"PCE", "PSF", "PCF", "PPC", "PLS",
"KCF", "KSF", "KCC", "KRS", "KIE", "KRB",
"TLF", "TSF", "TCF", "TPC", "SPI", "TLS",
"SBE", "SPL", "CAL",
"CLEI", "CLDI", "CLSC", "CLLE", "CLCL", "CLSK",
"CINT", "RDF", "RIF", "RIB",
"RMF", "SINT", "CUF", "SUF",
"ADCL", "ADLM", "ADST", "ADRB",
"ADSK", "ADSE", "ADLE", "ADRS",
"DCMA", "DMAR", "DMAW",
"DCIM", "DSAC", "DIML", "DIMA",
"DCEA", "DEAL", "DEAC",
"DFSE", "DFSC", "DISK", "DMAC",
"DCXA", "DXAL", "DXAC",
"PSKF", "PCLF", "PSKE",
"PSTB", "PSIE", "PCLF PSTB", "PCIE",
"LWCR", "CWCR", "LCAR",
"CCAR", "LCMR", "LFGR", "LDBR",
"RWCR", "CLT", "RCAR",
"RMSR", "RCMR", "RFSR", "RDBR",
"SKEF", "SKCB", "SKJD", "SKTR", "CLF",
"DSKP", "DCLR", "DLAG",
"DLCA", "DRST", "DLDC", "DMAN",
"LCD", "XDR", "STR",
"SER", "SDN", "INTR", "INIT",
"DTRA", "DTCA", "DTXA", "DTLA",
"DTSF", "DTRB", "DTLB",
"RLDC", "RLSD", "RLMA", "RLCA",
"RLCB", "RLSA", "RLWC",
"RRER", "RRWC", "RRCA", "RRCB",
"RRSA", "RRSI", "RLSE",
"ETDS", "ESKP", "ECTF", "ECDF",
"ERTB", "ESME", "ERIOT", "ETEN",
"CDF", "CIF", "CIF CDF",
"AND", "TAD", "ISZ", "DCA", "JMS", "JMP", "IOT",
"NOP", "NOP2", "NOP3", "SWAB", "SWBA",
"STL", "GLK", "STA", "LAS", "CIA",
"BSW", "RAL", "RTL", "RAR", "RTR", "RAL RAR", "RTL RTR",
"SKP", "SNL", "SZL",
"SZA", "SNA", "SZA SNL", "SNA SZL",
"SMA", "SPA", "SMA SNL", "SPA SZL",
"SMA SZA", "SPA SNA", "SMA SZA SNL", "SPA SNA SZL",
"SCL", "MUY", "DVI", "NMI", "SHL", "ASR", "LSR",
"SCA", "SCA SCL", "SCA MUY", "SCA DVI",
"SCA NMI", "SCA SHL", "SCA ASR", "SCA LSR",
"ACS", "MUY", "DVI", "NMI", "SHL", "ASR", "LSR",
"SCA", "DAD", "DST", "SWBA",
"DPSZ", "DPIC", "DCIM", "SAM",
"CLA", "CLL", "CMA", "CML", "IAC", /* encode only */
"CLA", "OAS", "HLT",
"CLA", "MQA", "MQL",
NULL, NULL, NULL, NULL, /* decode only */
NULL
};
static const int32 opc_val[] = {
06000+I_NPN, 06001+I_NPN, 06002+I_NPN, 06003+I_NPN,
06004+I_NPN, 06005+I_NPN, 06006+I_NPN, 06007+I_NPN,
06010+I_NPN, 06011+I_NPN, 06012+I_NPN, 06014+I_NPN, 06016+I_NPN,
06020+I_NPN, 06021+I_NPN, 06022+I_NPN, 06024+I_NPN, 06026+I_NPN,
06030+I_NPN, 06031+I_NPN, 06032+I_NPN, 06034+I_NPN, 06035+I_NPN, 06036+I_NPN,
06040+I_NPN, 06041+I_NPN, 06042+I_NPN, 06044+I_NPN, 06045+I_NPN, 06046+I_NPN,
06101+I_NPN, 06102+I_NPN, 06103+I_NPN,
06131+I_NPN, 06132+I_NPN, 06133+I_NPN, 06135+I_NPN, 06136+I_NPN, 06137+I_NPN,
06204+I_NPN, 06214+I_NPN, 06224+I_NPN, 06234+I_NPN,
06244+I_NPN, 06254+I_NPN, 06264+I_NPN, 06274+I_NPN,
06530+I_NPN, 06531+I_NPN, 06532+I_NPN, 06533+I_NPN,
06534+I_NPN, 06535+I_NPN, 06536+I_NPN, 06537+I_NPN,
06601+I_NPN, 06603+I_NPN, 06605+I_NPN,
06611+I_NPN, 06612+I_NPN, 06615+I_NPN, 06616+I_NPN,
06611+I_NPN, 06615+I_NPN, 06616+I_NPN,
06621+I_NPN, 06622+I_NPN, 06623+I_NPN, 06626+I_NPN,
06641+I_NPN, 06643+I_NPN, 06645+I_NPN,
06661+I_NPN, 06662+I_NPN, 06663+I_NPN,
06664+I_NPN, 06665+I_NPN, 06666+I_NPN, 06667+I_NPN,
06701+I_NPN, 06702+I_NPN, 06703+I_NPN,
06704+I_NPN, 06705+I_NPN, 06706+I_NPN, 06707+I_NPN,
06711+I_NPN, 06712+I_NPN, 06713+I_NPN,
06714+I_NPN, 06715+I_NPN, 06716+I_NPN, 06717+I_NPN,
06721+I_NPN, 06722+I_NPN, 06723+I_NPN, 06724+I_NPN, 06725+I_NPN,
06741+I_NPN, 06742+I_NPN, 06743+I_NPN,
06744+I_NPN, 06745+I_NPN, 06746+I_NPN, 06747+I_NPN,
06751+I_NPN, 06752+I_NPN, 06753+I_NPN,
06754+I_NPN, 06755+I_NPN, 06756+I_NPN, 06757+I_NPN,
06761+I_NPN, 06762+I_NPN, 06764+I_NPN, 06766+I_NPN,
06771+I_NPN, 06772+I_NPN, 06774+I_NPN,
06600+I_NPN, 06601+I_NPN, 06602+I_NPN, 06603+I_NPN,
06604+I_NPN, 06605+I_NPN, 06607+I_NPN,
06610+I_NPN, 06611+I_NPN, 06612+I_NPN, 06613+I_NPN,
06614+I_NPN, 06615+I_NPN, 06617+I_NPN,
06360+I_NPN, 06361+I_NPN, 06362+I_NPN, 06363+I_NPN,
06364+I_NPN, 06365+I_NPN, 06366+I_NPN, 06367+I_NPN,
06201+I_FLD, 06202+I_FLD, 06203+I_FLD,
00000+I_MRF, 01000+I_MRF, 02000+I_MRF, 03000+I_MRF,
04000+I_MRF, 05000+I_MRF, 06000+I_IOT,
07000+I_NPN, 07400+I_NPN, 07401+I_NPN, 07431+I_NPN, 07447+I_NPN,
07120+I_NPN, 07204+I_NPN, 07240+I_NPN, 07604+I_NPN, 07041+I_NPN,
07002+I_OP1, 07004+I_OP1, 07006+I_OP1,
07010+I_OP1, 07012+I_OP1, 07014+I_OP1, 07016+I_OP1,
07410+I_OP2, 07420+I_OP2, 07430+I_OP2,
07440+I_OP2, 07450+I_OP2, 07460+I_OP2, 07470+I_OP2,
07500+I_OP2, 07510+I_OP2, 07520+I_OP2, 07530+I_OP2,
07540+I_OP2, 07550+I_OP2, 07560+I_OP2, 07570+I_OP2,
07403+I_OP3, 07405+I_OP3, 07407+I_OP3,
07411+I_OP3, 07413+I_OP3, 07415+I_OP3, 07417+I_OP3,
07441+I_OP3, 07443+I_OP3, 07445+I_OP3, 07447+I_OP3,
07451+I_OP3, 07453+I_OP3, 07455+I_OP3, 07457+I_OP3,
017403+I_OP3, 017405+I_OP3, 0174017+I_OP3,
017411+I_OP3, 017413+I_OP3, 017415+I_OP3, 017417+I_OP3,
017441+I_OP3, 017443+I_OP3, 017445+I_OP3, 017447+I_OP3,
017451+I_OP3, 017453+I_OP3, 017455+I_OP3, 017457+I_OP3,
07200+I_OP1, 07100+I_OP1, 07040+I_OP1, 07020+I_OP1, 07001+I_OP1,
07600+I_OP2, 07404+I_OP2, 07402+I_OP2,
07601+I_OP3, 07501+I_OP3, 07421+I_OP3,
07000+I_OP1, 07400+I_OP2, 07401+I_OP3, 017401+I_OP3,
-1
};
/* Operate decode
Inputs:
*of = output stream
inst = mask bits
class = instruction class code
sp = space needed?
Outputs:
status = space needed
*/
int32 fprint_opr (FILE *of, int32 inst, int32 class, int32 sp)
{
int32 i, j;
for (i = 0; opc_val[i] >= 0; i++) { /* loop thru ops */
j = (opc_val[i] >> I_V_FL) & I_M_FL; /* get class */
if ((j == class) && (opc_val[i] & inst)) { /* same class? */
inst = inst & ~opc_val[i]; /* mask bit set? */
fprintf (of, (sp? " %s": "%s"), opcode[i]);
sp = 1;
}
}
return sp;
}
/* Symbolic decode
Inputs:
*of = output stream
addr = current PC
*val = pointer to data
*uptr = pointer to unit
sw = switches
Outputs:
return = status code
*/
#define FMTASC(x) ((x) < 040)? "<%03o>": "%c", (x)
#define SIXTOASC(x) (((x) >= 040)? (x): (x) + 0100)
#define TSSTOASC(x) ((x) + 040)
t_stat fprint_sym (FILE *of, t_addr addr, t_value *val,
UNIT *uptr, int32 sw)
{
int32 cflag, i, j, sp, inst, disp;
extern int32 emode;
cflag = (uptr == NULL) || (uptr == &cpu_unit);
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 ('C')) { /* characters? */
fprintf (of, "%c", SIXTOASC ((inst >> 6) & 077));
fprintf (of, "%c", SIXTOASC (inst & 077));
return SCPE_OK;
}
if (sw & SWMASK ('T')) { /* TSS8 packed? */
fprintf (of, "%c", TSSTOASC ((inst >> 6) & 077));
fprintf (of, "%c", TSSTOASC (inst & 077));
return SCPE_OK;
}
if (!(sw & SWMASK ('M'))) return SCPE_ARG;
/* Instruction decode */
inst = val[0] | ((emode & 1) << 12); /* include EAE mode */
for (i = 0; opc_val[i] >= 0; i++) { /* loop thru ops */
j = (opc_val[i] >> I_V_FL) & I_M_FL; /* get class */
if ((opc_val[i] & 017777) == (inst & masks[j])) { /* match? */
switch (j) { /* case on class */
case I_V_NPN: /* no operands */
fprintf (of, "%s", opcode[i]); /* opcode */
break;
case I_V_FLD: /* field change */
fprintf (of, "%s %-o", opcode[i], (inst >> 3) & 07);
break;
case I_V_MRF: /* mem ref */
disp = inst & 0177; /* displacement */
fprintf (of, "%s%s", opcode[i], ((inst & 00400)? " I ": " "));
if (inst & 0200) { /* current page? */
if (cflag) fprintf (of, "%-o", (addr & 07600) | disp);
else fprintf (of, "C %-o", disp);
}
else fprintf (of, "%-o", disp); /* page zero */
break;
case I_V_IOT: /* IOT */
fprintf (of, "%s %-o", opcode[i], inst & 0777);
break;
case I_V_OP1: /* operate group 1 */
sp = fprint_opr (of, inst & 0361, j, 0);
if (opcode[i]) fprintf (of, (sp? " %s": "%s"), opcode[i]);
break;
case I_V_OP2: /* operate group 2 */
if (opcode[i]) fprintf (of, "%s", opcode[i]); /* skips */
fprint_opr (of, inst & 0206, j, opcode[i] != NULL);
break;
case I_V_OP3: /* operate group 3 */
sp = fprint_opr (of, inst & 0320, j, 0);
if (opcode[i]) fprintf (of, (sp? " %s": "%s"), opcode[i]);
break;
} /* end case */
return SCPE_OK;
} /* end if */
} /* end for */
return SCPE_ARG;
}
/* 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 (char *cptr, t_addr addr, UNIT *uptr, t_value *val, int32 sw)
{
int32 cflag, d, i, j, k;
t_stat r;
char gbuf[CBUFSIZE];
cflag = (uptr == NULL) || (uptr == &cpu_unit);
while (isspace (*cptr)) cptr++; /* absorb spaces */
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] | 0200;
return SCPE_OK;
}
if ((sw & SWMASK ('C')) || ((*cptr == '"') && cptr++)) { /* sixbit string? */
if (cptr[0] == 0) return SCPE_ARG; /* must have 1 char */
val[0] = (((t_value) cptr[0] & 077) << 6) |
((t_value) cptr[1] & 077);
return SCPE_OK;
}
if ((sw & SWMASK ('T')) || ((*cptr == '"') && cptr++)) { /* TSS8 string? */
if (cptr[0] == 0) return SCPE_ARG; /* must have 1 char */
val[0] = (((t_value) (cptr[0] - 040) & 077) << 6) |
((t_value) (cptr[1] - 040) & 077);
return SCPE_OK;
}
/* Instruction parse */
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] & 07777; /* get value */
j = (opc_val[i] >> I_V_FL) & I_M_FL; /* get class */
switch (j) { /* case on class */
case I_V_IOT: /* IOT */
cptr = get_glyph (cptr, gbuf, 0); /* get dev+pulse */
d = get_uint (gbuf, 8, 0777, &r);
if (r != SCPE_OK) return SCPE_ARG;
val[0] = val[0] | d;
break;
case I_V_FLD: /* field */
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] >> I_V_FL) & I_M_FL;
if (k != j) return SCPE_ARG;
val[0] = val[0] | (opc_val[i] & 07777);
}
else {
d = get_uint (gbuf, 8, 07, &r);
if (r != SCPE_OK) return SCPE_ARG;
val[0] = val[0] | (d << 3);
break;
}
}
break;
case I_V_MRF: /* mem ref */
cptr = get_glyph (cptr, gbuf, 0); /* get next field */
if (strcmp (gbuf, "I") == 0) { /* indirect? */
val[0] = val[0] | 0400;
cptr = get_glyph (cptr, gbuf, 0);
}
if ((k = (strcmp (gbuf, "C") == 0)) || (strcmp (gbuf, "Z") == 0)) {
cptr = get_glyph (cptr, gbuf, 0);
d = get_uint (gbuf, 8, 0177, &r);
if (r != SCPE_OK) return SCPE_ARG;
val[0] = val[0] | d | (k? 0200: 0);
}
else {
d = get_uint (gbuf, 8, 07777, &r);
if (r != SCPE_OK) return SCPE_ARG;
if (d <= 0177) val[0] = val[0] | d;
else if (cflag && (((addr ^ d) & 07600) == 0))
val[0] = val[0] | (d & 0177) | 0200;
else return SCPE_ARG;
}
break;
case I_V_NPN: case I_V_OP1: case I_V_OP2: case I_V_OP3: /* operates */
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++) ;
k = opc_val[i] & 07777;
if ((opcode[i] == NULL) || (((k ^ val[0]) & 07000) != 0))
return SCPE_ARG;
val[0] = val[0] | k;
}
break;
} /* end case */
if (*cptr != 0) return SCPE_ARG; /* junk at end? */
return SCPE_OK;
}