simh-testsetgenerator/Interdata/id_mt.c
Bob Supnik 26aa6de663 Notes For V3.2-0
RESTRICTION: The PDP-15 FPP is only partially debugged.  Do NOT
enable this feature for normal operations.

WARNING: The core simulator files (scp.c, sim_*.c) have been
reorganized.  Unzip V3.2-0 to an empty directory before attempting
to compile the source.

IMPORTANT: If you are compiling for UNIX, please read the notes
for Ethernet very carefully.  You may need to download a new
version of the pcap library, or make changes to the makefile,
to get Ethernet support to work.

1. New Features in 3.2-0

1.1 SCP and libraries

- Added SHOW <device> RADIX command.
- Added SHOW <device> MODIFIERS command.
- Added SHOW <device> NAMES command.
- Added SET/SHOW <device> DEBUG command.
- Added sim_vm_parse_addr and sim_vm_fprint_addr optional interfaces.
- Added REG_VMAD flag.
- Split SCP into separate libraries for easier modification.
- Added more room to the device and unit flag fields.
- Changed terminal multiplexor library to support unlimited.
  number of async lines.

1.2 All DECtapes

- Added STOP_EOR flag to enable end-of-reel error stop
- Added device debug support.

1.3 Nova and Eclipse

- Added QTY and ALM multiplexors (Bruce Ray).

1.4 LGP-30

- Added LGP-30/LGP-21 simulator.

1.5 PDP-11

- Added format, address increment inhibit, transfer overrun
  detection to RK.
- Added device debug support to HK, RP, TM, TQ, TS.
- Added DEUNA/DELUA (XU) support (Dave Hittner).
- Add DZ per-line logging.

1.6 18b PDP's

- Added support for 1-4 (PDP-9)/1-16 (PDP-15) additional
  terminals.

1.7 PDP-10

- Added DEUNA/DELUA (XU) support (Dave Hittner).

1.8 VAX

- Added extended memory to 512MB (Mark Pizzolato).
- Added RXV21 support.

2. Bugs Fixed in 3.2-0

2.1 SCP

- Fixed double logging of SHOW BREAK (found by Mark Pizzolato).
- Fixed implementation of REG_VMIO.

2.2 Nova and Eclipse

- Fixed device enable/disable support (found by Bruce Ray).

2.3 PDP-1

- Fixed bug in LOAD (found by Mark Crispin).

2.4 PDP-10

- Fixed bug in floating point unpack.
- Fixed bug in FIXR (found by Phil Stone, fixed by Chris Smith).

2.6 PDP-11

- Fixed bug in RQ interrupt control (found by Tom Evans).

2.6 PDP-18B

- Fixed bug in PDP-15 XVM g_mode implementation.
- Fixed bug in PDP-15 indexed address calculation.
- Fixed bug in PDP-15 autoindexed address calculation.
- Fixed bugs in FPP-15 instruction decode.
- Fixed clock response to CAF.
- Fixed bug in hardware read-in mode bootstrap.
- Fixed PDP-15 XVM instruction decoding errors.

2.7 VAX

- Fixed PC read fault in EXTxV.
- Fixed PC write fault in INSV.
2011-04-15 08:34:26 -07:00

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/* id_mt.c: Interdata magnetic tape simulator
Copyright (c) 2001-2004, 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.
mt M46-494 dual density 9-track magtape controller
25-Apr-03 RMS Revised for extended file support
28-Mar-03 RMS Added multiformat support
28-Feb-03 RMS Revised for magtape library
20-Feb-03 RMS Fixed read to stop selch on error
Magnetic tapes are represented as a series of variable 8b records
of the form:
32b record length in bytes - exact number
byte 0
byte 1
:
byte n-2
byte n-1
32b record length in bytes - exact number
If the byte count is odd, the record is padded with an extra byte
of junk. File marks are represented by a single record length of 0.
End of tape is two consecutive end of file marks.
*/
#include "id_defs.h"
#include "sim_tape.h"
#define UST u3 /* unit status */
#define UCMD u4 /* unit command */
#define MT_MAXFR (1 << 16) /* max transfer */
/* Command - in UCMD */
#define MTC_SPCR 0x11 /* backspace */
#define MTC_SKFR 0x13 /* space file rev */
#define MTC_CLR 0x20 /* clear */
#define MTC_RD 0x21 /* read */
#define MTC_WR 0x22 /* write */
#define MTC_SKFF 0x23 /* space file fwd */
#define MTC_WEOF 0x30 /* write eof */
#define MTC_REW 0x38 /* rewind */
#define MTC_MASK 0x3F
#define MTC_STOP1 0x40 /* stop, set EOM */
#define MTC_STOP2 0x80 /* stop, set NMTN */
/* Status byte, * = in UST */
#define STA_ERR 0x80 /* error */
#define STA_EOF 0x40 /* end of file */
#define STA_EOT 0x20 /* *end of tape */
#define STA_NMTN 0x10 /* *no motion */
#define STA_UFLGS (STA_EOT|STA_NMTN) /* unit flags */
#define STA_MASK (STA_ERR|STA_EOF|STA_BSY|STA_EOM)
#define SET_EX (STA_ERR|STA_EOF|STA_NMTN)
extern uint32 int_req[INTSZ], int_enb[INTSZ];
uint8 mtxb[MT_MAXFR]; /* xfer buffer */
uint32 mt_bptr = 0; /* pointer */
uint32 mt_blnt = 0; /* length */
uint32 mt_sta = 0; /* status byte */
uint32 mt_db = 0; /* data buffer */
uint32 mt_xfr = 0; /* data xfr in prog */
uint32 mt_arm[MT_NUMDR] = { 0 }; /* intr armed */
int32 mt_wtime = 10; /* byte latency */
int32 mt_rtime = 1000; /* record latency */
int32 mt_stopioe = 1; /* stop on error */
uint8 mt_tplte[] = { 0, o_MT0, o_MT0*2, o_MT0*3, TPL_END };
static const uint8 bad_cmd[64] = {
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1 };
DEVICE mt_dev;
uint32 mt (uint32 dev, uint32 op, uint32 dat);
t_stat mt_svc (UNIT *uptr);
t_stat mt_reset (DEVICE *dptr);
t_stat mt_attach (UNIT *uptr, char *cptr);
t_stat mt_detach (UNIT *uptr);
t_stat mt_boot (int32 unitno, DEVICE *dptr);
t_stat mt_map_err (UNIT *uptr, t_stat st);
/* MT data structures
mt_dev MT device descriptor
mt_unit MT unit list
mt_reg MT register list
mt_mod MT modifier list
*/
DIB mt_dib = { d_MT, 0, v_MT, mt_tplte, &mt, NULL };
UNIT mt_unit[] = {
{ UDATA (&mt_svc, UNIT_ATTABLE + UNIT_DISABLE, 0) },
{ UDATA (&mt_svc, UNIT_ATTABLE + UNIT_DISABLE, 0) },
{ UDATA (&mt_svc, UNIT_ATTABLE + UNIT_DISABLE, 0) },
{ UDATA (&mt_svc, UNIT_ATTABLE + UNIT_DISABLE, 0) } };
REG mt_reg[] = {
{ HRDATA (STA, mt_sta, 8) },
{ HRDATA (BUF, mt_db, 8) },
{ BRDATA (DBUF, mtxb, 16, 8, MT_MAXFR) },
{ HRDATA (DBPTR, mt_bptr, 16) },
{ HRDATA (DBLNT, mt_blnt, 17), REG_RO },
{ FLDATA (XFR, mt_xfr, 0) },
{ GRDATA (IREQ, int_req[l_MT], 16, MT_NUMDR, i_MT) },
{ GRDATA (IENB, int_enb[l_MT], 16, MT_NUMDR, i_MT) },
{ BRDATA (IARM, mt_arm, 16, 1, MT_NUMDR) },
{ FLDATA (STOP_IOE, mt_stopioe, 0) },
{ DRDATA (WTIME, mt_wtime, 24), PV_LEFT + REG_NZ },
{ DRDATA (RTIME, mt_rtime, 24), PV_LEFT + REG_NZ },
{ URDATA (UST, mt_unit[0].UST, 16, 8, 0, MT_NUMDR, 0) },
{ URDATA (CMD, mt_unit[0].UCMD, 16, 8, 0, MT_NUMDR, 0) },
{ URDATA (POS, mt_unit[0].pos, 10, T_ADDR_W, 0,
MT_NUMDR, PV_LEFT | REG_RO) },
{ HRDATA (DEVNO, mt_dib.dno, 8), REG_HRO },
{ HRDATA (SELCH, mt_dib.sch, 1), REG_HRO },
{ NULL } };
MTAB mt_mod[] = {
{ MTUF_WLK, 0, "write enabled", "WRITEENABLED", NULL },
{ MTUF_WLK, MTUF_WLK, "write locked", "LOCKED", NULL },
{ MTAB_XTD|MTAB_VUN, 0, "FORMAT", "FORMAT",
&sim_tape_set_fmt, &sim_tape_show_fmt, NULL },
{ MTAB_XTD|MTAB_VDV, 0, "DEVNO", "DEVNO",
&set_dev, &show_dev, NULL },
{ MTAB_XTD|MTAB_VDV, 0, "SELCH", "SELCH",
&set_sch, &show_sch, NULL },
{ 0 } };
DEVICE mt_dev = {
"MT", mt_unit, mt_reg, mt_mod,
MT_NUMDR, 10, 31, 1, 16, 8,
NULL, NULL, &mt_reset,
&mt_boot, &mt_attach, &mt_detach,
&mt_dib, DEV_DISABLE };
/* Magtape: IO routine */
uint32 mt (uint32 dev, uint32 op, uint32 dat)
{
uint32 i, f, t;
uint32 u = (dev - mt_dib.dno) / o_MT0;
UNIT *uptr = mt_dev.units + u;
switch (op) { /* case IO op */
case IO_ADR: /* select */
sch_adr (mt_dib.sch, dev); /* inform sel ch */
return BY; /* byte only */
case IO_RD: /* read data */
if (mt_xfr) mt_sta = mt_sta | STA_BSY; /* xfr? set busy */
return mt_db; /* return data */
case IO_WD: /* write data */
if (mt_xfr) { /* transfer? */
mt_sta = mt_sta | STA_BSY; /* set busy */
if ((uptr->UCMD & (MTC_STOP1 | MTC_STOP2)) &&
((uptr->UCMD & MTC_MASK) == MTC_WR)) /* while stopping? */
mt_sta = mt_sta | STA_ERR; } /* write overrun */
mt_db = dat & DMASK8; /* store data */
break;
case IO_SS: /* status */
mt_sta = mt_sta & STA_MASK; /* ctrl status */
if (uptr->flags & UNIT_ATT) /* attached? */
t = mt_sta | (uptr->UST & STA_UFLGS); /* yes, unit status */
else t = mt_sta | STA_DU; /* no, dev unavail */
if (t & SET_EX) t = t | STA_EX; /* test for ex */
return t;
case IO_OC: /* command */
mt_arm[u] = int_chg (v_MT + u, dat, mt_arm[u]);
f = dat & MTC_MASK; /* get cmd */
if (f == MTC_CLR) { /* clear? */
mt_reset (&mt_dev); /* reset world */
break; }
if (((uptr->flags & UNIT_ATT) == 0) || /* ignore if unatt */
bad_cmd[f] || /* or bad cmd */
(((f == MTC_WR) || (f == MTC_WEOF)) && /* or write */
sim_tape_wrp (uptr))) break; /* and protected */
for (i = 0; i < MT_NUMDR; i++) { /* check other drvs */
if (sim_is_active (&mt_unit[i]) && /* active? */
(mt_unit[i].UCMD != MTC_REW)) { /* not rewind? */
sim_cancel (&mt_unit[i]); /* stop */
mt_unit[i].UCMD = 0; }
if (sim_is_active (uptr) && /* unit active? */
!(uptr->UCMD & (MTC_STOP1 | MTC_STOP2))) /* not stopping? */
break; /* ignore */
if ((f == MTC_WR) || (f == MTC_REW)) mt_sta = 0;/* write, rew: bsy=0 */
else mt_sta = STA_BSY; /* bsy=1,nmtn,eom,err=0 */
mt_bptr = mt_blnt = 0; /* not yet started */
if ((f == MTC_RD) || (f == MTC_WR)) /* data xfr? */
mt_xfr = 1; /* set xfr flag */
else mt_xfr = 0; }
uptr->UCMD = f; /* save cmd */
uptr->UST = 0; /* clr tape stat */
sim_activate (uptr, mt_rtime); /* start op */
break; }
return 0;
}
/* Unit service
A given operation can generate up to three interrupts
- EOF generates an interrupt when set (read, space, wreof)
BUSY will still be set, EOM and NMTN will be clear
- After operation complete + delay, EOM generates an interrupt
BUSY will be clear, EOM will be set, NMTN will be clear
- After a further delay, NMTN generates an interrupt
BUSY will be clear, EOM and NMTN will be set
Rewind generates an interrupt when NMTN sets
*/
t_stat mt_svc (UNIT *uptr)
{
uint32 i;
int32 u = uptr - mt_dev.units;
uint32 dev = mt_dib.dno + (u * o_MT0);
t_mtrlnt tbc;
t_stat st, r = SCPE_OK;
if ((uptr->flags & UNIT_ATT) == 0) { /* not attached? */
uptr->UCMD = 0; /* clr cmd */
uptr->UST = 0; /* set status */
mt_xfr = 0; /* clr op flags */
mt_sta = STA_ERR | STA_EOM; /* set status */
if (mt_arm[u]) SET_INT (v_MT + u); /* interrupt */
return IORETURN (mt_stopioe, SCPE_UNATT); }
if (uptr->UCMD & MTC_STOP2) { /* stop, gen NMTN? */
uptr->UCMD = 0; /* clr cmd */
uptr->UST = STA_NMTN; /* set nmtn, not eot */
mt_xfr = 0; /* clr xfr */
if (mt_arm[u]) SET_INT (v_MT + u); /* set intr */
return SCPE_OK; }
if (uptr->UCMD & MTC_STOP1) { /* stop, gen EOM? */
uptr->UCMD = uptr->UCMD | MTC_STOP2; /* clr cmd */
mt_sta = (mt_sta & ~STA_BSY) | STA_EOM; /* clr busy, set eom */
if (mt_arm[u]) SET_INT (v_MT + u); /* set intr */
sim_activate (uptr, mt_rtime); /* schedule */
return SCPE_OK; } /* end case */
switch (uptr->UCMD) { /* case on function */
case MTC_REW: /* rewind */
sim_tape_rewind (uptr); /* reposition */
uptr->UCMD = 0; /* clr cmd */
uptr->UST = STA_NMTN | STA_EOT; /* update status */
mt_sta = mt_sta & ~STA_BSY; /* don't set EOM */
if (mt_arm[u]) SET_INT (v_MT + u); /* interrupt */
return SCPE_OK;
/* Unit service, continued
For read, busy = 1 => buffer empty
For write, busy = 1 => buffer full
For read, data transfers continue for the full length of the
record, or the maximum size of the transfer buffer
For write, data transfers continue until a write is attempted
and the buffer is empty
*/
case MTC_RD: /* read */
if (mt_blnt == 0) { /* first time? */
st = sim_tape_rdrecf (uptr, mtxb, &tbc, MT_MAXFR); /* read rec */
if (st == MTSE_RECE) mt_sta = mt_sta | STA_ERR; /* rec in err? */
else if (st != SCPE_OK) { /* other error? */
r = mt_map_err (uptr, st); /* map error */
if (sch_actv (mt_dib.sch, dev)) /* if sch, stop */
sch_stop (mt_dib.sch);
break; }
mt_blnt = tbc; /* set buf lnt */
}
if (sch_actv (mt_dib.sch, dev)) { /* sch active? */
i = sch_wrmem (mt_dib.sch, mtxb, mt_blnt); /* store rec in mem */
if (sch_actv (mt_dib.sch, dev)) /* sch still active? */
sch_stop (mt_dib.sch); /* stop chan, long rd */
else if (i < mt_blnt) /* process entire rec? */
mt_sta = mt_sta | STA_ERR; } /* no, overrun error */
else if (mt_bptr < mt_blnt) { /* no, if !eor */
if (!(mt_sta & STA_BSY)) /* busy still clr? */
mt_sta = mt_sta | STA_ERR; /* read overrun */
mt_db = mtxb[mt_bptr++]; /* get next byte */
mt_sta = mt_sta & ~STA_BSY; /* !busy = buf full */
if (mt_arm[u]) SET_INT (v_MT + u); /* set intr */
sim_activate (uptr, mt_wtime); /* reschedule */
return SCPE_OK; }
break; /* record done */
case MTC_WR: /* write */
if (sch_actv (mt_dib.sch, dev)) { /* sch active? */
mt_bptr = sch_rdmem (mt_dib.sch, mtxb, MT_MAXFR); /* get rec */
if (sch_actv (mt_dib.sch, dev)) /* not done? */
sch_stop (mt_dib.sch); } /* stop chan */
else if (mt_sta & STA_BSY) { /* no, if !eor */
if (mt_bptr < MT_MAXFR) /* if room */
mtxb[mt_bptr++] = mt_db; /* store in buf */
mt_sta = mt_sta & ~STA_BSY; /* !busy = buf emp */
if (mt_arm[u]) SET_INT (v_MT + u); /* set intr */
sim_activate (uptr, mt_wtime); /* reschedule */
return SCPE_OK; }
if (mt_bptr) { /* any chars? */
if (st = sim_tape_wrrecf (uptr, mtxb, mt_bptr)) /* write, err? */
r = mt_map_err (uptr, st); } /* map error */
break; /* record done */
/* Unit service, continued */
case MTC_WEOF: /* write eof */
if (st = sim_tape_wrtmk (uptr)) /* write tmk, err? */
r = mt_map_err (uptr, st); /* map error */
mt_sta = mt_sta | STA_EOF; /* set eof */
if (mt_arm[u]) SET_INT (v_MT + u); /* interrupt */
break;
case MTC_SKFF: /* skip file fwd */
while ((st = sim_tape_sprecf (uptr, &tbc)) == MTSE_OK) ;
if (st == MTSE_TMK) { /* stopped by tmk? */
mt_sta = mt_sta | STA_EOF; /* set eof */
if (mt_arm[u]) SET_INT (v_MT + u); } /* set intr */
else r = mt_map_err (uptr, st); /* map error */
break;
case MTC_SKFR: /* skip file rev */
while ((st = sim_tape_sprecr (uptr, &tbc)) == MTSE_OK) ;
if (st == MTSE_TMK) { /* stopped by tmk? */
mt_sta = mt_sta | STA_EOF; /* set eof */
if (mt_arm[u]) SET_INT (v_MT + u); } /* set intr */
else r = mt_map_err (uptr, st); /* map error */
break;
case MTC_SPCR: /* backspace */
if (st = sim_tape_sprecr (uptr, &tbc)) /* skip rec rev, err? */
r = mt_map_err (uptr, st); /* map error */
break; } /* end case */
uptr->UCMD = uptr->UCMD | MTC_STOP1; /* set stop stage 1 */
sim_activate (uptr, mt_rtime); /* schedule */
return r;
}
/* Map tape error status */
t_stat mt_map_err (UNIT *uptr, t_stat st)
{
int32 u = uptr - mt_dev.units;
switch (st) {
case MTSE_FMT: /* illegal fmt */
case MTSE_UNATT: /* not attached */
mt_sta = mt_sta | STA_ERR;
case MTSE_OK: /* no error */
return SCPE_IERR;
case MTSE_TMK: /* end of file */
mt_sta = mt_sta | STA_EOF; /* set eof */
if (mt_arm[u]) SET_INT (v_MT + u); /* set intr */
break;
case MTSE_IOERR: /* IO error */
mt_sta = mt_sta | STA_ERR; /* set err */
if (mt_stopioe) return SCPE_IOERR;
break;
case MTSE_INVRL: /* invalid rec lnt */
mt_sta = mt_sta | STA_ERR;
return SCPE_MTRLNT;
case MTSE_WRP: /* write protect */
case MTSE_RECE: /* record in error */
case MTSE_EOM: /* end of medium */
mt_sta = mt_sta | STA_ERR; /* set err */
break;
case MTSE_BOT: /* reverse into BOT */
uptr->UST = uptr->UST | STA_EOT; /* set err */
break; } /* end switch */
return SCPE_OK;
}
/* Reset routine */
t_stat mt_reset (DEVICE *dptr)
{
uint32 u;
UNIT *uptr;
mt_bptr = mt_blnt = 0; /* clr buf */
mt_sta = STA_BSY; /* clr flags */
mt_xfr = 0; /* clr controls */
for (u = 0; u < MT_NUMDR; u++) { /* loop thru units */
CLR_INT (v_MT + u); /* clear int */
CLR_ENB (v_MT + u); /* disable int */
mt_arm[u] = 0; /* disarm int */
uptr = mt_dev.units + u;
sim_tape_reset (uptr); /* clear pos flag */
sim_cancel (uptr); /* cancel activity */
uptr->UST = (uptr->UST & STA_UFLGS) | STA_NMTN; /* init status */
uptr->UCMD = 0; } /* init cmd */
return SCPE_OK;
}
/* Attach routine */
t_stat mt_attach (UNIT *uptr, char *cptr)
{
int32 u = uptr - mt_dev.units;
t_stat r;
r = sim_tape_attach (uptr, cptr);
if (r != SCPE_OK) return r;
uptr->UST = STA_EOT;
if (mt_arm[u]) SET_INT (v_MT + u);
return r;
}
/* Detach routine */
t_stat mt_detach (UNIT* uptr)
{
int32 u = uptr - mt_dev.units;
t_stat r;
r = sim_tape_detach (uptr);
if (r != SCPE_OK) return r;
if (mt_arm[u]) SET_INT (v_MT + u);
uptr->UST = 0;
return SCPE_OK;
}
/* Bootstrap routine */
#define BOOT_START 0x50
#define BOOT_LEN (sizeof (boot_rom) / sizeof (uint8))
static uint8 boot_rom[] = {
0xD5, 0x00, /* ST: AL CF */
0x00, 0xCF,
0x43, 0x00, /* BR 80 */
0x00, 0x80
};
t_stat mt_boot (int32 unitno, DEVICE *dptr)
{
extern uint32 PC, dec_flgs;
extern uint16 decrom[];
extern DIB sch_dib;
uint32 sch_dev;
if (decrom[0xD5] & dec_flgs) return SCPE_NOFNC; /* AL defined? */
sim_tape_rewind (&mt_unit[unitno]); /* rewind */
sch_dev = sch_dib.dno + mt_dib.sch; /* sch dev # */
IOWriteBlk (BOOT_START, BOOT_LEN, boot_rom); /* copy boot */
IOWriteB (AL_DEV, mt_dib.dno + (unitno * o_MT0)); /* set dev no for unit */
IOWriteB (AL_IOC, 0xA1); /* set dev cmd */
IOWriteB (AL_SCH, sch_dev); /* set dev no for chan */
PC = BOOT_START;
return SCPE_OK;
}