/* i1401_mt.c: IBM 1401 magnetic tape simulator Copyright (c) 1993-2022, 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 26-Mar-22 RMS Added extra case points for new MTSE definitions 20-Oct-16 RMS Must call sim_tape_attach to use library (Mark Pizzolato) 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[] = { { MTAB_XTD|MTAB_VUN, 0, "write enabled", "WRITEENABLED", &set_writelock, &show_writelock, NULL, "Write enable tape drive" }, { MTAB_XTD|MTAB_VUN, 1, NULL, "LOCKED", &set_writelock, NULL, NULL, "Write lock tape drive" }, { 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, &sim_tape_attach, &sim_tape_detach, NULL, DEV_DEBUG | DEV_TAPE }; /* 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 */ default: /* unknown error */ 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; }