/* pdp11_kg.c - Communications Arithmetic Option KG11-A | |
Copyright (c) 2007-2010, John A. Dundas III | |
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 the author shall not be | |
used in advertising or otherwise to promote the sale, use or other dealings | |
in this Software without prior written authorization from the author. | |
kg KG11-A Communications Arithmetic Option (M7251) | |
03-Jan-10 JAD Eliminate gcc warnings | |
08-Jan-08 JAD First public release integrated with SIMH V3.7-3. | |
09-Dec-07 JAD SIMH-style debugging. | |
Finished validating against real hardware. | |
Support for up to 8 units, the maximum. | |
Keep all module data in the UNIT structure. | |
Clean up bit and mask definitions. | |
01-Dec-07 JAD Now work on the corner cases that the | |
diagnostic does not check. | |
CLR does not clear the QUO bit. | |
Correct SR write logic. | |
29-Nov-07 JAD Original implementation and testing based on | |
an idea from 07-Jul-03. Passes the ZKGAB0 | |
diagnostic. | |
Information necessary to create this simulation was gathered from | |
a number of sources including: | |
KG11-A Exclusive-OR and CRC block check manual, DEC-11-HKGAA-B-D | |
<http://www.computer.museum.uq.edu.au/pdf/DEC-11-HKGAA-B-D%20KG11-A%20Exclusive-OR%20and%20CRC%20Block%20Check%20Manual.pdf> | |
Maintenance print set | |
<http://bitsavers.org/pdf/dec/unibus/KG11A_EngrDrws.pdf> | |
A Painless Guide to CRC Error Detection Algorithms, Ross N. Williams | |
<http://www.ross.net/crc/download/crc_v3.txt"> | |
The original PDP-11 instruction set, as implemented in the /20, | |
/15, /10, and /5, did not include XOR. [One of the differences | |
tables incorrectly indicates the /04 does not implement this | |
instruction.] This device implements XOR, XORB, and a variety of | |
CRCs. | |
The maintenance prints indicate that the device was probably available | |
starting in late 1971. May need to check further. The first edition | |
of the manual was May 1972. | |
The device was still sold at least as late as mid-1982 according | |
to the PDP-11 Systems and Options Summary. RSTS/E included support | |
for up to 8 units in support of the 2780 emulation or for use with | |
DP11, DU11, or DUP11. The device appears to have been retired by | |
1983-03, and possibly earlier. | |
I/O Page Registers | |
SR 7707x0 (read-write) status | |
BCC 7707x2 (read-only) BCC (block check character) | |
DR 7707x4 (write-only) data | |
Vector: none | |
Priority: none | |
The KG11-A is a programmed-I/O, non-interrupting device. Therefore | |
no vector or bus request level are necessary. It is a Unibus device | |
but since it does not address memory itself (it only presents | |
registers in the I/O page) it is compatible with extended Unibus | |
machines (22-bit) as well as traditional Unibus. | |
Implements 5 error detection codes: | |
LRC-8 | |
LRC-16 | |
CRC-12 | |
CRC-16 | |
CRC-CCITT | |
*/ | |
#if !defined (VM_PDP11) | |
#error "KG11 is not supported!" | |
#endif | |
#include "pdp11_defs.h" | |
extern REG cpu_reg[]; | |
extern int32 R[]; | |
#ifndef KG_UNITS | |
#define KG_UNITS (8) | |
#endif | |
/* Control and Status Register */ | |
#define KGSR_V_QUO (8) /* RO */ | |
#define KGSR_V_DONE (7) /* RO */ | |
#define KGSR_V_SEN (6) /* R/W shift enable */ | |
#define KGSR_V_STEP (5) /* W */ | |
#define KGSR_V_CLR (4) /* W */ | |
#define KGSR_V_DDB (3) /* R/W double data byte */ | |
#define KGSR_V_CRCIC (2) /* R/W */ | |
#define KGSR_V_LRC (1) /* R/W */ | |
#define KGSR_V_16 (0) /* R/W */ | |
#define KGSR_M_QUO (1u << KGSR_V_QUO) | |
#define KGSR_M_DONE (1u << KGSR_V_DONE) | |
#define KGSR_M_SEN (1u << KGSR_V_SEN) | |
#define KGSR_M_STEP (1u << KGSR_V_STEP) | |
#define KGSR_M_CLR (1u << KGSR_V_CLR) | |
#define KGSR_M_DDB (1u << KGSR_V_DDB) | |
#define KGSR_M_CRCIC (1u << KGSR_V_CRCIC) | |
#define KGSR_M_LRC (1u << KGSR_V_LRC) | |
#define KGSR_M_16 (1u << KGSR_V_16) | |
#define KG_SR_RDMASK (KGSR_M_QUO | KGSR_M_DONE | KGSR_M_SEN | KGSR_M_DDB | \ | |
KGSR_M_CRCIC | KGSR_M_LRC | KGSR_M_16) | |
#define KG_SR_WRMASK (KGSR_M_SEN | KGSR_M_DDB | KGSR_M_CRCIC | \ | |
KGSR_M_LRC | KGSR_M_16) | |
#define KG_SR_POLYMASK (KGSR_M_CRCIC|KGSR_M_LRC|KGSR_M_16) | |
#define POLY_LRC8 (0x0008) | |
#define POLY_LRC16 (0x0080) | |
#define POLY_CRC12 (0x0f01) | |
#define POLY_CRC16 (0xa001) | |
#define POLY_CCITT (0x8408) | |
static const struct { | |
uint16 poly; | |
uint16 pulses; | |
const char * const name; | |
} config[] = { | |
/* DDB=0 */ | |
{ POLY_CRC12, 6, "CRC-12" }, | |
{ POLY_CRC16, 8, "CRC-16" }, | |
{ POLY_LRC8, 8, "LRC-8" }, | |
{ POLY_LRC16, 8, "LRC-16" }, | |
{ 0, 0, "undefined" }, | |
{ POLY_CCITT, 8, "CRC-CCITT" }, | |
{ 0, 0, "undefined" }, | |
{ 0, 0, "undefined" }, | |
/* DDB=1 */ | |
{ POLY_CRC12, 12, "CRC-12" }, | |
{ POLY_CRC16, 16, "CRC-16" }, | |
{ POLY_LRC8, 16, "LRC-8" }, | |
{ POLY_LRC16, 16, "LRC-16" }, | |
{ 0, 0, "undefined" }, | |
{ POLY_CCITT, 16, "CRC-CCITT" }, | |
{ 0, 0, "undefined" }, | |
{ 0, 0, "undefined" } | |
}; | |
/* Forward declarations */ | |
static t_stat kg_rd (int32 *, int32, int32); | |
static t_stat kg_wr (int32, int32, int32); | |
static t_stat kg_reset (DEVICE *); | |
static void do_poly (int, t_bool); | |
static t_stat set_units (UNIT *, int32, CONST char *, void *); | |
t_stat kg_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr); | |
const char *kg_description (DEVICE *dptr); | |
/* 16-bit rotate right */ | |
#define ROR(n,v) (((v >> n) & DMASK) | ((v << (16 - n)) & DMASK)) | |
/* 8-bit rotate right */ | |
#define RORB(n,v) (((v & 0377) >> n) | ((v << (8 - n)) & 0377)) | |
/* KG data structures | |
kg_dib KG PDP-11 device information block | |
kg_unit KG unit descriptor | |
kg_reg KG register list | |
kg_mod KG modifiers table | |
kg_debug KG debug names table | |
kg_dev KG device descriptor | |
*/ | |
#define IOLN_KG 006 | |
static DIB kg_dib = { | |
IOBA_AUTO, | |
(IOLN_KG + 2) * KG_UNITS, | |
&kg_rd, | |
&kg_wr, | |
0, 0, 0, { NULL }, IOLN_KG+2 | |
}; | |
static UNIT kg_unit[KG_UNITS]; | |
static const REG kg_reg[] = { | |
{ URDATAD (SR, kg_unit[0].u3, DEV_RDX, 16, 0, KG_UNITS, 0, "control and status register; R/W") }, | |
{ URDATAD (BCC, kg_unit[0].u4, DEV_RDX, 16, 0, KG_UNITS, 0, "result block check character; R/O") }, | |
{ URDATAD (DR, kg_unit[0].u5, DEV_RDX, 16, 0, KG_UNITS, 0, "input data register; W/O") }, | |
{ URDATAD (PULSCNT, kg_unit[0].u6, DEV_RDX, 16, 0, KG_UNITS, 0, "polynomial cycle stage") }, | |
{ ORDATA (DEVADDR, kg_dib.ba, 32), REG_HRO }, | |
{ NULL } | |
}; | |
/* Unit structure redefinitions */ | |
#define SR u3 | |
#define BCC u4 | |
#define DR u5 | |
#define PULSCNT u6 | |
static const MTAB kg_mod[] = { | |
{ MTAB_XTD|MTAB_VDV|MTAB_VALR, 020, "ADDRESS", NULL, | |
NULL, &show_addr, NULL, "Bus address" }, | |
{ MTAB_XTD|MTAB_VDV, 0, NULL, "UNITS=1..8", | |
&set_units, NULL, NULL, "Specify number of KG devices" }, | |
{ 0 } | |
}; | |
#define DBG_REG (01) | |
#define DBG_POLY (02) | |
#define DBG_CYCLE (04) | |
static const DEBTAB kg_debug[] = { | |
{"REG", DBG_REG}, | |
{"POLY", DBG_POLY}, | |
{"CYCLE", DBG_CYCLE}, | |
{0}, | |
}; | |
DEVICE kg_dev = { | |
"KG", (UNIT *) &kg_unit, (REG *) kg_reg, (MTAB *) kg_mod, | |
KG_UNITS, 8, 16, 2, 8, 16, | |
NULL, /* examine */ | |
NULL, /* deposit */ | |
&kg_reset, /* reset */ | |
NULL, /* boot */ | |
NULL, /* attach */ | |
NULL, /* detach */ | |
&kg_dib, | |
DEV_DISABLE | DEV_DIS | DEV_UBUS | DEV_DEBUG, | |
0, /* debug control */ | |
(DEBTAB *) &kg_debug, /* debug flags */ | |
NULL, /* memory size chage */ | |
NULL, /* logical name */ | |
&kg_help, /* help */ | |
NULL, /* attach help */ | |
NULL, /* help context */ | |
&kg_description, /* description */ | |
}; | |
/* KG I/O address routines */ | |
static t_stat kg_rd (int32 *data, int32 PA, int32 access) | |
{ | |
int unit = (PA >> 3) & 07; | |
if ((unit >= KG_UNITS) || (kg_unit[unit].flags & UNIT_DIS)) | |
return (SCPE_NXM); | |
switch ((PA >> 1) & 03) { | |
case 00: /* SR */ | |
if (DEBUG_PRI(kg_dev, DBG_REG)) | |
fprintf (sim_deb, ">>KG%d: rd SR %06o, PC %06o\n", | |
unit, kg_unit[unit].SR, PC); | |
*data = kg_unit[unit].SR & KG_SR_RDMASK; | |
break; | |
case 01: /* BCC */ | |
if (DEBUG_PRI(kg_dev, DBG_REG)) | |
fprintf (sim_deb, ">>KG%d rd BCC %06o, PC %06o\n", | |
unit, kg_unit[unit].BCC, PC); | |
*data = kg_unit[unit].BCC & DMASK; | |
break; | |
case 02: /* DR */ | |
break; | |
default: | |
break; | |
} | |
return (SCPE_OK); | |
} | |
static t_stat kg_wr (int32 data, int32 PA, int32 access) | |
{ | |
int setup; | |
int unit = (PA >> 3) & 07; | |
if ((unit >= KG_UNITS) || (kg_unit[unit].flags & UNIT_DIS)) | |
return (SCPE_NXM); | |
switch ((PA >> 1) & 03) { | |
case 00: /* SR */ | |
if (access == WRITEB) | |
data = (PA & 1) ? | |
(kg_unit[unit].SR & 0377) | (data << 8) : | |
(kg_unit[unit].SR & ~0377) | data; | |
if (DEBUG_PRI(kg_dev, DBG_REG)) | |
fprintf (sim_deb, ">>KG%d: wr SR %06o, PC %06o\n", | |
unit, data, PC); | |
if (data & KGSR_M_CLR) { | |
kg_unit[unit].PULSCNT = 0; /* not sure about this */ | |
kg_unit[unit].BCC = 0; | |
kg_unit[unit].SR |= KGSR_M_DONE; | |
} | |
setup = (kg_unit[unit].SR & 017) ^ (data & 017); | |
kg_unit[unit].SR = (kg_unit[unit].SR & ~KG_SR_WRMASK) | | |
(data & KG_SR_WRMASK); | |
/* if low 4b changed, reset C1 & C2 */ | |
if (setup) { | |
kg_unit[unit].PULSCNT = 0; | |
if (DEBUG_PRI(kg_dev, DBG_POLY)) | |
fprintf (sim_deb, ">>KG%d poly %s %d\n", | |
unit, config[data & 017].name, config[data & 017].pulses); | |
} | |
if (data & KGSR_M_SEN) | |
break; | |
if (data & KGSR_M_STEP) { | |
do_poly (unit, TRUE); | |
break; | |
} | |
break; | |
case 01: /* BCC */ | |
break; /* ignored */ | |
case 02: /* DR */ | |
if (access == WRITEB) | |
data = (PA & 1) ? | |
(kg_unit[unit].DR & 0377) | (data << 8) : | |
(kg_unit[unit].DR & ~0377) | data; | |
kg_unit[unit].DR = data & DMASK; | |
if (DEBUG_PRI(kg_dev, DBG_REG)) | |
fprintf (sim_deb, ">>KG%d: wr DR %06o, data %06o, PC %06o\n", | |
unit, kg_unit[unit].DR, data, PC); | |
kg_unit[unit].SR &= ~KGSR_M_DONE; | |
/* In a typical device, this is normally where we would use sim_activate() | |
to initiate an I/O to be completed later. The KG is a little | |
different. When it was first introduced, it's computation operation | |
completed before another instruction could execute (on early PDP-11s), | |
and software often took "advantage" of this fact by not bothering | |
to check the status of the DONE bit. In reality, the execution | |
time of the polynomial is dependent upon the width of the poly; if | |
8 bits 1us, if 16 bits, 2us. Since known existing software will | |
break if we actually defer the computation, it is performed immediately | |
instead. However this could easily be made into a run-time option, | |
if there were software to validate correct operation. */ | |
if (kg_unit[unit].SR & KGSR_M_SEN) | |
do_poly (unit, FALSE); | |
break; | |
default: | |
break; | |
} | |
return (SCPE_OK); | |
} | |
/* KG reset */ | |
static t_stat kg_reset (DEVICE *dptr) | |
{ | |
int i; | |
if (DEBUG_PRI(kg_dev, DBG_REG)) | |
fprintf (sim_deb, ">>KG: reset PC %06o\n", PC); | |
for (i = 0; i < KG_UNITS; i++) { | |
kg_unit[i].SR = KGSR_M_DONE; | |
kg_unit[i].BCC = 0; | |
kg_unit[i].PULSCNT = 0; | |
kg_unit[i].flags |= UNIT_DISABLE; /* allow SET KGn DISABLE */ | |
} | |
return auto_config(dptr->name, (dptr->flags & DEV_DIS) ? 0 : kg_dev.numunits); | |
} | |
static void cycleOneBit (int unit) | |
{ | |
int quo; | |
if (DEBUG_PRI(kg_dev, DBG_CYCLE)) | |
fprintf (sim_deb, ">>KG%d: cycle s BCC %06o DR %06o\n", | |
unit, kg_unit[unit].BCC, kg_unit[unit].DR); | |
if (kg_unit[unit].SR & KGSR_M_DONE) | |
return; | |
if ((kg_unit[unit].SR & KG_SR_POLYMASK) == 0) | |
kg_unit[unit].BCC = (kg_unit[unit].BCC & 077) | | |
((kg_unit[unit].BCC >> 2) & 07700); | |
kg_unit[unit].SR &= ~KGSR_M_QUO; | |
quo = (kg_unit[unit].BCC & 01) ^ (kg_unit[unit].DR & 01); | |
kg_unit[unit].BCC = (kg_unit[unit].BCC & ~01) | quo; | |
if (kg_unit[unit].SR & KGSR_M_LRC) | |
kg_unit[unit].BCC = (kg_unit[unit].SR & KGSR_M_16) ? | |
ROR(1, kg_unit[unit].BCC) : | |
RORB(1, kg_unit[unit].BCC); | |
else | |
kg_unit[unit].BCC = (kg_unit[unit].BCC & 01) ? | |
(kg_unit[unit].BCC >> 1) ^ config[kg_unit[unit].SR & 07].poly : | |
kg_unit[unit].BCC >> 1; | |
kg_unit[unit].DR >>= 1; | |
kg_unit[unit].SR |= quo << KGSR_V_QUO; | |
if ((kg_unit[unit].SR & KG_SR_POLYMASK) == 0) | |
kg_unit[unit].BCC = (kg_unit[unit].BCC & 077) | | |
((kg_unit[unit].BCC & 07700) << 2); | |
kg_unit[unit].PULSCNT++; | |
if (kg_unit[unit].PULSCNT >= config[kg_unit[unit].SR & 017].pulses) | |
kg_unit[unit].SR |= KGSR_M_DONE; | |
if (DEBUG_PRI(kg_dev, DBG_CYCLE)) | |
fprintf (sim_deb, ">>KG%d: cycle e BCC %06o DR %06o\n", | |
unit, kg_unit[unit].BCC, kg_unit[unit].DR); | |
} | |
static void do_poly (int unit, t_bool step) | |
{ | |
if (kg_unit[unit].SR & KGSR_M_DONE) | |
return; | |
if (step) | |
cycleOneBit (unit); | |
else { | |
while (!(kg_unit[unit].SR & KGSR_M_DONE)) | |
cycleOneBit (unit); | |
} | |
} | |
static t_stat set_units (UNIT *u, int32 val, CONST char *s, void *desc) | |
{ | |
uint32 i, units; | |
t_stat stat; | |
if (s == NULL) | |
return (SCPE_ARG); | |
units = get_uint (s, 10, KG_UNITS, &stat); | |
if (stat != SCPE_OK) | |
return (stat); | |
if (units == 0) | |
return SCPE_ARG; | |
if (units == kg_dev.numunits) | |
return SCPE_OK; | |
for (i = 0; i < KG_UNITS; i++) { | |
if (i < units) | |
kg_unit[i].flags &= ~UNIT_DIS; | |
else | |
kg_unit[i].flags |= UNIT_DIS; | |
} | |
kg_dev.numunits = units; | |
kg_dib.lnt = (IOLN_KG + 2) * units; | |
kg_reset (&kg_dev); | |
return (SCPE_OK); | |
} | |
t_stat kg_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr) | |
{ | |
const char *const text = | |
/*567901234567890123456789012345678901234567890123456789012345678901234567890*/ | |
" KG11-A Communications Arithmetic Option (KG)\n" | |
"\n" | |
" The KG11-A is a programmed I/O, non-interrupting, dedicated arithmetic\n" | |
" processor for the Unibus. The device is used to compute the block check\n" | |
" character (BCC) over a block of data, typically in data communication\n" | |
" applications. The KG11 can compute three different Cyclic Redundancy\n" | |
" Check (CRC) polynomials (CRC-16, CRC-12, CRC-CCITT) and two Longitudinal\n" | |
" Redundancy Checks (LRC, Exclusive-OR; LRC-8, LRC-16). Up to eight units\n" | |
" may be contiguously present in a single machine and are all located at\n" | |
" fixed addresses. This simulation implements all functionality of the\n" | |
" device including the ability to single step computation of the BCC.\n" | |
" The KG is disabled by default.\n" | |
/*567901234567890123456789012345678901234567890123456789012345678901234567890*/ | |
"\n"; | |
fprintf (st, "%s", text); | |
fprint_set_help (st, dptr); | |
fprint_show_help (st, dptr); | |
fprint_reg_help (st, dptr); | |
return SCPE_OK; | |
} | |
const char *kg_description (DEVICE *dptr) | |
{ | |
return "KG11-A Communications Arithmetic Option"; | |
} |