/* i1401_mt.c: IBM 1401 magnetic tape simulator | |
Copyright (c) 1993-2011, 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 | |
03-Sep-13 RMS Read TMK does not write GM+WM to memory | |
19-Mar-11 RMS Restored lost edit to insert EOF in memory on read EOF | |
Reverted multiple tape indicator implementation | |
20-Jan-11 RMS Fixed branch on END indicator per hardware (Van Snyder) | |
26-Jun-10 RMS Fixed backspace over tapemark not to set EOR (Van Snyder) | |
11-Jul-08 RMS Added -n (no rewind) option to BOOT (Van Snyder) | |
Added tape mark detect to diagnostic read (Bob Abeles) | |
Added tape mark detect in multi-character records (Bob Abeles) | |
Fixed memory leak in tape rewind-unload op (Bob Abeles) | |
Fixed bug, BOOT ignores GM+WM in memory (Bob Abeles) | |
Fixed handling of indicators (Bob Abeles) | |
Fixed bug to mask input to 6b on read (Bob Abeles) | |
07-Jul-07 RMS Removed restriction on load-mode binary tape | |
28-Jun-07 RMS Revised read tape mark behavior based on real hardware | |
(Van Snyder) | |
16-Feb-06 RMS Added tape capacity checking | |
15-Sep-05 RMS Yet another fix to load read group mark plus word mark | |
Added debug printouts (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 | |
(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 (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. | |
(Notes on indicators from Bob Abeles) | |
The 1401 implements a "tape indicator" latch per tape drive. When a | |
1401 branch-on-indicator instruction addresses the "end-of-reel" | |
indicator, the 1401 addresses the "tape indicator" latch in the | |
currently selected and ready tape drive. The tape drive itself resets | |
its "tape indicator" latch only when a tape unload occurs. Tape | |
unload may be initiated by push button control or by the CPU "Rewind | |
Tape and Unload" instruction. The tape drive sets the "tape | |
indicator" latch when in write status and the end-of-reel reflective | |
strip photocell is activated. The CPU resets the "tape indicator" | |
latch in the selected and ready tape drive when the "end-of-reel" | |
indicator is tested by a branch-on-indicator instruction. If no tape | |
drive is selected, or the currently selected tape drive is not ready, | |
the "end-of-reel" indicator will appear to be off and no "tape | |
indicator" latch will be reset. The CPU sets the "tape indicator" | |
latch in the selected and ready tape drive whenever it reads a tape- | |
mark character in the first character position of a record. | |
*/ | |
#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; | |
t_stat mt_reset (DEVICE *dptr); | |
t_stat mt_boot (int32 unitno, DEVICE *dptr); | |
t_stat mt_map_status (t_stat st); | |
UNIT *mt_sel_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 (IND, 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 }, | |
{ MTAB_XTD|MTAB_VUN, 0, "CAPACITY", "CAPACITY", | |
&sim_tape_set_capac, &sim_tape_show_capac, 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, NULL, NULL, | |
NULL, DEV_DEBUG | |
}; | |
/* Function routine | |
Inputs: | |
unit = unit character | |
flag = normal, word mark, binary, or boot mode | |
mod = modifier character | |
Outputs: | |
status = status | |
*/ | |
t_stat mt_func (int32 unit, int32 flag, int32 mod) | |
{ | |
t_mtrlnt tbc; | |
UNIT *uptr; | |
t_stat st; | |
if ((uptr = mt_sel_unit (unit)) == NULL) /* sel unit, save */ | |
return STOP_INVMTU; /* (not valid) */ | |
if ((uptr->flags & UNIT_ATT) == 0) /* attached? */ | |
return SCPE_UNATT; | |
ind[IN_TAP] = 0; /* clear error */ | |
ind[IN_END] = 0; /* clear indicator */ | |
switch (mod) { /* case on modifier */ | |
case BCD_A: /* diagnostic read */ | |
if (DEBUG_PRS (mt_dev)) | |
fprintf (sim_deb, ">>MT%d: diagnostic read\n", unit); | |
st = sim_tape_rdrecf (uptr, dbuf, &tbc, MT_MAXFR); /* read rec */ | |
if (st != MTSE_TMK) { /* not tmk? */ | |
if (st == MTSE_RECE) /* rec in error? */ | |
ind[IN_TAP] = 1; | |
else if (st != MTSE_OK) { /* stop on error */ | |
if (DEBUG_PRS (mt_dev)) | |
fprintf (sim_deb, ", stopped by status = %d\n", st); | |
break; | |
} | |
if (!(flag & MD_BIN) && /* BCD tape and */ | |
((dbuf[0] & CHAR) == BCD_TAPMRK)) /* first char TMK? */ | |
ind[IN_END] = 1; /* set indicator */ | |
} | |
break; | |
case BCD_B: /* backspace */ | |
if (DEBUG_PRS (mt_dev)) | |
fprintf (sim_deb, ">>MT%d: backspace\n", unit); | |
st = sim_tape_sprecr (uptr, &tbc); /* space rev */ | |
if (st == MTSE_TMK) /* ignore TMK */ | |
st = MTSE_OK; | |
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)) /* write protected? */ | |
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 sim_tape_detach (uptr); /* detach */ | |
default: | |
return STOP_INVM; | |
} | |
return mt_map_status (st); | |
} | |
/* Read and write routines | |
Inputs: | |
unit = unit character | |
flag = normal, word mark, binary, or boot 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; | |
t_bool passed_eot; | |
UNIT *uptr; | |
if ((uptr = mt_sel_unit (unit)) == NULL) /* sel unit, save */ | |
return STOP_INVMTU; /* (not valid) */ | |
if ((uptr->flags & UNIT_ATT) == 0) /* attached? */ | |
return SCPE_UNATT; | |
ind[IN_TAP] = 0; /* clear error */ | |
ind[IN_END] = 0; /* clear indicator */ | |
switch (mod) { | |
case BCD_R: /* read */ | |
if (DEBUG_PRS (mt_dev)) | |
fprintf (sim_deb, ">>MT%d: read from %d", unit, BS); | |
wm_seen = 0; /* no word mk seen */ | |
st = sim_tape_rdrecf (uptr, dbuf, &tbc, MT_MAXFR); /* read rec */ | |
if (st == MTSE_TMK) { /* tape mark? */ | |
ind[IN_END] = 1; /* set indicator */ | |
tbc = 1; /* one char read */ | |
dbuf[0] = BCD_TAPMRK; /* BCD tapemark */ | |
} | |
else { /* not tmk? */ | |
if (st == MTSE_RECE) /* rec in error? */ | |
ind[IN_TAP] = 1; | |
else if (st != MTSE_OK) { /* stop on error */ | |
if (DEBUG_PRS (mt_dev)) | |
fprintf (sim_deb, ", stopped by status = %d\n", st); | |
break; | |
} | |
if (!(flag & MD_BIN) && /* BCD tape and */ | |
((dbuf[0] & CHAR) == BCD_TAPMRK)) /* first char TMK? */ | |
ind[IN_END] = 1; /* set indicator */ | |
} | |
for (i = 0; i < tbc; i++) { /* loop thru buf */ | |
if (!(flag & MD_BOOT) && /* not boot? check */ | |
(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] & CHAR; /* get char, strip parity */ | |
if (!(flag & MD_BIN) && (t == BCD_ALT)) /* BCD mode alt blank? */ | |
t = BCD_BLANK; /* real blank */ | |
if (flag & MD_WM) { /* word mk mode? */ | |
if ((t == BCD_WM) && (wm_seen == 0)) /* WM char, none prev? */ | |
wm_seen = WM; /* set flag */ | |
else { | |
M[BS] = wm_seen | (t & CHAR); /* char + wm seen */ | |
wm_seen = 0; /* clear flag */ | |
} | |
} | |
else M[BS] = (M[BS] & WM) | (t & CHAR); /* preserve mem WM */ | |
if (!wm_seen) | |
BS++; | |
if (ADDR_ERR (BS)) { /* check next BS */ | |
BS = BA | (BS % MAXMEMSIZE); | |
return STOP_WRAP; | |
} | |
} | |
if (st == MTSE_TMK) /* if TMK, no GM+WM */ | |
break; | |
if (M[BS] != (BCD_GRPMRK + WM)) { /* not GM+WM at end? */ | |
if (flag & MD_WM) /* LCA: clear WM */ | |
M[BS] = BCD_GRPMRK; | |
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)) /* locked? */ | |
return STOP_MTL; | |
if (M[BS] == (BCD_GRPMRK + WM)) /* eor? */ | |
return STOP_MTZ; | |
if (DEBUG_PRS (mt_dev)) | |
fprintf (sim_deb, ">>MT%d: write from %d", unit, BS); | |
for (tbc = 0; (t = M[BS++]) != (BCD_GRPMRK + WM); ) { | |
if ((t & WM) && (flag & MD_WM)) /* WM in wm mode? */ | |
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); | |
passed_eot = sim_tape_eot (uptr); /* passed EOT? */ | |
st = sim_tape_wrrecf (uptr, dbuf, tbc); /* write record */ | |
if (!passed_eot && sim_tape_eot (uptr)) /* just passed EOT? */ | |
ind[IN_END] = 1; | |
if (ADDR_ERR (BS)) { /* check final BS */ | |
BS = BA | (BS % MAXMEMSIZE); | |
return STOP_WRAP; | |
} | |
break; | |
default: | |
return STOP_INVM; | |
} | |
return mt_map_status (st); | |
} | |
/* Select unit - return unit pointer if valid */ | |
UNIT *mt_sel_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 indicator */ | |
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++) { /* per drive resets */ | |
if ((uptr = mt_sel_unit (i))) { | |
MT_CLR_PNU (uptr); /* clear pos flag */ | |
} | |
} | |
ind[IN_TAP] = 0; /* clear mt err ind */ | |
ind[IN_END] = 0; /* clear mt end ind */ | |
return SCPE_OK; | |
} | |
/* Bootstrap routine | |
The 1401 Reference manual states, "...tape data starts loading at address 001 | |
and continues until an inter-record gap is sensed." GM+WM in memory is ignored. | |
*/ | |
t_stat mt_boot (int32 unitno, DEVICE *dptr) | |
{ | |
extern int32 saved_IS; | |
if ((sim_switches & SWMASK ('N')) == 0) /* unless -n */ | |
sim_tape_rewind (&mt_unit[unitno]); /* force rewind */ | |
BS = 1; /* set BS = 001 */ | |
mt_io (unitno, MD_WM + MD_BOOT, BCD_R); /* LDA %U1 001 R */ | |
saved_IS = 1; | |
return SCPE_OK; | |
} |