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/* i1401_mt.c: IBM 1401 magnetic tape simulator
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.
mt 7-track magtape
15-Sep-05 RMS Yet another fix to load read group mark plus word mark
Added debug printouts (from Van Snyder)
26-Aug-05 RMS Revised to use API for write lock check
16-Aug-03 RMS End-of-record on load read works like move read
(verified on real 1401)
Added diagnostic read (space forward)
25-Apr-03 RMS Revised for extended file support
28-Mar-03 RMS Added multiformat support
15-Mar-03 RMS Fixed end-of-record on load read yet again
28-Feb-03 RMS Modified for magtape library
31-Oct-02 RMS Added error record handling
10-Oct-02 RMS Fixed end-of-record on load read writes WM plus GM
30-Sep-02 RMS Revamped error handling
28-Aug-02 RMS Added end of medium support
12-Jun-02 RMS End-of-record on move read preserves old WM under GM
(found by Van Snyder)
03-Jun-02 RMS Modified for 1311 support
30-May-02 RMS Widened POS to 32b
22-Apr-02 RMS Added protection against bad record lengths
30-Jan-02 RMS New zero footprint tape bootstrap from Van Snyder
20-Jan-02 RMS Changed write enabled modifier
29-Nov-01 RMS Added read only unit support
18-Apr-01 RMS Changed to rewind tape before boot
07-Dec-00 RMS Widened display width from 6 to 8 bits to see record lnt
CEO Added tape bootstrap
14-Apr-99 RMS Changed t_addr to unsigned
04-Oct-98 RMS V2.4 magtape format
Magnetic tapes are represented as a series of variable 16b records
of the form:
32b byte count
byte 0
byte 1
:
byte n-2
byte n-1
32b byte count
If the byte count is odd, the record is padded with an extra byte
of junk. File marks are represented by a byte count of 0.
*/
#include "i1401_defs.h"
#include "sim_tape.h"
#define MT_NUMDR 7 /* #drives */
#define MT_MAXFR (MAXMEMSIZE * 2) /* max transfer */
uint8 dbuf[MT_MAXFR]; /* tape buffer */
extern uint8 M[]; /* memory */
extern int32 ind[64];
extern int32 BS, iochk;
extern UNIT cpu_unit;
extern FILE *sim_deb;
t_stat mt_reset (DEVICE *dptr);
t_stat mt_boot (int32 unitno, DEVICE *dptr);
t_stat mt_map_status (t_stat st);
UNIT *get_unit (int32 unit);
/* MT data structures
mt_dev MT device descriptor
mt_unit MT unit list
mt_reg MT register list
mt_mod MT modifier list
*/
UNIT mt_unit[] = {
{ UDATA (NULL, UNIT_DIS, 0) }, /* doesn't exist */
{ UDATA (NULL, UNIT_DISABLE + UNIT_ATTABLE +
UNIT_ROABLE + UNIT_BCD, 0) },
{ UDATA (NULL, UNIT_DISABLE + UNIT_ATTABLE +
UNIT_ROABLE + UNIT_BCD, 0) },
{ UDATA (NULL, UNIT_DISABLE + UNIT_ATTABLE +
UNIT_ROABLE + UNIT_BCD, 0) },
{ UDATA (NULL, UNIT_DISABLE + UNIT_ATTABLE +
UNIT_ROABLE + UNIT_BCD, 0) },
{ UDATA (NULL, UNIT_DISABLE + UNIT_ATTABLE +
UNIT_ROABLE + UNIT_BCD, 0) },
{ UDATA (NULL, UNIT_DISABLE + UNIT_ATTABLE +
UNIT_ROABLE + UNIT_BCD, 0) }
};
REG mt_reg[] = {
{ FLDATA (END, ind[IN_END], 0) },
{ FLDATA (ERR, ind[IN_TAP], 0) },
{ DRDATA (POS1, mt_unit[1].pos, T_ADDR_W), PV_LEFT + REG_RO },
{ DRDATA (POS2, mt_unit[2].pos, T_ADDR_W), PV_LEFT + REG_RO },
{ DRDATA (POS3, mt_unit[3].pos, T_ADDR_W), PV_LEFT + REG_RO },
{ DRDATA (POS4, mt_unit[4].pos, T_ADDR_W), PV_LEFT + REG_RO },
{ DRDATA (POS5, mt_unit[5].pos, T_ADDR_W), PV_LEFT + REG_RO },
{ DRDATA (POS6, mt_unit[6].pos, T_ADDR_W), PV_LEFT + REG_RO },
{ 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 },
{ 0 }
};
DEVICE mt_dev = {
"MT", mt_unit, mt_reg, mt_mod,
MT_NUMDR, 10, 31, 1, 8, 8,
NULL, NULL, &mt_reset,
&mt_boot, &sim_tape_attach, &sim_tape_detach,
NULL, DEV_DEBUG
};
/* Function routine
Inputs:
unit = unit character
mod = modifier character
Outputs:
status = status
*/
t_stat mt_func (int32 unit, int32 mod)
{
t_mtrlnt tbc;
UNIT *uptr;
t_stat st;
if ((uptr = get_unit (unit)) == NULL) return STOP_INVMTU; /* valid unit? */
if ((uptr->flags & UNIT_ATT) == 0) return SCPE_UNATT; /* attached? */
switch (mod) { /* case on modifier */
case BCD_A: /* diagnostic read */
if (DEBUG_PRS (mt_dev)) fprintf (sim_deb,
">>MT%d: diagnostic read\n", unit);
ind[IN_END] = 0; /* clear end of file */
st = sim_tape_sprecf (uptr, &tbc); /* space fwd */
break;
case BCD_B: /* backspace */
if (DEBUG_PRS (mt_dev)) fprintf (sim_deb,
">>MT%d: backspace\n", unit);
ind[IN_END] = 0; /* clear end of file */
st = sim_tape_sprecr (uptr, &tbc); /* space rev */
break; /* end case */
case BCD_E: /* erase = nop */
if (DEBUG_PRS (mt_dev)) fprintf (sim_deb,
">>MT%d: erase\n", unit);
if (sim_tape_wrp (uptr)) return STOP_MTL;
return SCPE_OK;
case BCD_M: /* write tapemark */
if (DEBUG_PRS (mt_dev)) fprintf (sim_deb,
">>MT%d: write tape mark\n", unit);
st = sim_tape_wrtmk (uptr); /* write tmk */
break;
case BCD_R: /* rewind */
if (DEBUG_PRS (mt_dev)) fprintf (sim_deb,
">>MT%d: rewind\n", unit);
sim_tape_rewind (uptr); /* update position */
return SCPE_OK;
case BCD_U: /* unload */
if (DEBUG_PRS (mt_dev)) fprintf (sim_deb,
">>MT%d: rewind and unload\n", unit);
sim_tape_rewind (uptr); /* update position */
return detach_unit (uptr); /* detach */
default:
return STOP_INVM;
}
return mt_map_status (st);
}
/* Read and write routines
Inputs:
unit = unit character
flag = normal, word mark, or binary mode
mod = modifier character
Outputs:
status = status
Fine point: after a read, the system writes a group mark just
beyond the end of the record. However, first it checks for a
GM + WM; if present, the GM + WM is not changed. Otherwise,
an MCW read sets a GM, preserving the current WM; while an LCA
read sets a GM and clears the WM.
*/
t_stat mt_io (int32 unit, int32 flag, int32 mod)
{
int32 t, wm_seen;
t_mtrlnt i, tbc;
t_stat st;
UNIT *uptr;
if ((uptr = get_unit (unit)) == NULL) return STOP_INVMTU; /* valid unit? */
if ((uptr->flags & UNIT_ATT) == 0) return SCPE_UNATT; /* attached? */
switch (mod) {
case BCD_R: /* read */
if (DEBUG_PRS (mt_dev))
fprintf (sim_deb, ">>MT%d: read from %d", unit, BS);
ind[IN_TAP] = ind[IN_END] = 0; /* clear error */
wm_seen = 0; /* no word mk seen */
st = sim_tape_rdrecf (uptr, dbuf, &tbc, MT_MAXFR); /* read rec */
if (st == MTSE_RECE) ind[IN_TAP] = 1; /* rec in error? */
else if (st != MTSE_OK) { /* stop on error */
if (DEBUG_PRS (mt_dev))
fprintf (sim_deb, ", stopped by status = %d\n", st);
break;
}
for (i = 0; i < tbc; i++) { /* loop thru buf */
if (M[BS] == (BCD_GRPMRK + WM)) { /* GWM in memory? */
if (DEBUG_PRS (mt_dev))
fprintf (sim_deb, " to %d, stopped by GMWM\n", BS);
BS++; /* incr BS */
if (ADDR_ERR (BS)) { /* test for wrap */
BS = BA | (BS % MAXMEMSIZE);
return STOP_WRAP;
}
return SCPE_OK; /* done */
}
t = dbuf[i]; /* get char */
if ((flag != MD_BIN) && (t == BCD_ALT)) t = BCD_BLANK;
if (flag == MD_WM) { /* word mk mode? */
if ((t == BCD_WM) && (wm_seen == 0)) wm_seen = WM;
else {
M[BS] = wm_seen | (t & CHAR);
wm_seen = 0;
}
}
else M[BS] = (M[BS] & WM) | (t & CHAR);
if (!wm_seen) BS++;
if (ADDR_ERR (BS)) { /* check next BS */
BS = BA | (BS % MAXMEMSIZE);
return STOP_WRAP;
}
}
if (M[BS] != (BCD_GRPMRK + WM)) { /* not GM+WM at end? */
if (flag == MD_WM) M[BS] = BCD_GRPMRK; /* LCA: clear WM */
else M[BS] = (M[BS] & WM) | BCD_GRPMRK; /* MCW: save WM */
}
if (DEBUG_PRS (mt_dev))
fprintf (sim_deb, " to %d, stopped by EOR\n", BS);
BS++; /* adv BS */
if (ADDR_ERR (BS)) { /* check final BS */
BS = BA | (BS % MAXMEMSIZE);
return STOP_WRAP;
}
break;
case BCD_W:
if (sim_tape_wrp (uptr)) return STOP_MTL; /* locked? */
if (M[BS] == (BCD_GRPMRK + WM)) return STOP_MTZ;/* eor? */
if (DEBUG_PRS (mt_dev))
fprintf (sim_deb, ">>MT%d: write from %d", unit, BS);
ind[IN_TAP] = ind[IN_END] = 0; /* clear error */
for (tbc = 0; (t = M[BS++]) != (BCD_GRPMRK + WM); ) {
if ((t & WM) && (flag == MD_WM)) dbuf[tbc++] = BCD_WM;
if (((t & CHAR) == BCD_BLANK) && (flag != MD_BIN))
dbuf[tbc++] = BCD_ALT;
else dbuf[tbc++] = t & CHAR;
if (ADDR_ERR (BS)) { /* check next BS */
BS = BA | (BS % MAXMEMSIZE);
return STOP_WRAP;
}
}
if (DEBUG_PRS (mt_dev)) fprintf (sim_deb, " to %d\n", BS - 1);
st = sim_tape_wrrecf (uptr, dbuf, tbc); /* write record */
if (ADDR_ERR (BS)) { /* check final BS */
BS = BA | (BS % MAXMEMSIZE);
return STOP_WRAP;
}
break;
default:
return STOP_INVM;
}
return mt_map_status (st);
}
/* Get unit pointer from unit number */
UNIT *get_unit (int32 unit)
{
if ((unit <= 0) || (unit >= MT_NUMDR)) return NULL;
return mt_dev.units + unit;
}
/* Map tape status */
t_stat mt_map_status (t_stat st)
{
switch (st) {
case MTSE_OK: /* no error */
case MTSE_BOT: /* reverse into BOT */
break;
case MTSE_FMT: /* illegal fmt */
return SCPE_IERR;
case MTSE_UNATT: /* not attached */
return SCPE_UNATT;
case MTSE_INVRL: /* invalid rec lnt */
return SCPE_MTRLNT;
case MTSE_TMK: /* end of file */
ind[IN_END] = 1; /* set end mark */
break;
case MTSE_IOERR: /* IO error */
ind[IN_TAP] = 1; /* set error */
if (iochk) return SCPE_IOERR;
break;
case MTSE_RECE: /* record in error */
case MTSE_EOM: /* end of medium */
ind[IN_TAP] = 1; /* set error */
break;
case MTSE_WRP: /* write protect */
return STOP_MTL;
}
return SCPE_OK;
}
/* Reset routine */
t_stat mt_reset (DEVICE *dptr)
{
int32 i;
UNIT *uptr;
for (i = 0; i < MT_NUMDR; i++) { /* clear pos flag */
if (uptr = get_unit (i)) MT_CLR_PNU (uptr);
}
ind[IN_END] = ind[IN_TAP] = 0; /* clear indicators */
return SCPE_OK;
}
/* Bootstrap routine */
t_stat mt_boot (int32 unitno, DEVICE *dptr)
{
extern int32 saved_IS;
sim_tape_rewind (&mt_unit[unitno]); /* force rewind */
BS = 1; /* set BS = 001 */
mt_io (unitno, MD_WM, BCD_R); /* LDA %U1 001 R */
saved_IS = 1;
return SCPE_OK;
}