simh-testsetgenerator/HP2100/hp2100_dr.c
Bob Supnik 1da2d9452d Notes For V3.1-0
RESTRICTION: The FP15 and XVM features of the PDP-15 are only partially
debugged.  Do NOT enable these features for normal operations.

1. New Features in 3.1-0

1.1 SCP and libraries

- Added simulated Ethernet support for VMS, FreeBSD, Mac OS/X.
- Added status return to tmxr_putc_ln.
- Added sim_putchar_s to handle possible output stalls.

1.2 All DECtapes

- Added "DECtape off reel" error stop.

1.3 All Asynchronous Consoles

- Added support for output congestion stall if using a Telnet connection.

1.4 PDP-1

- Added Type 23 parallel drum support.

1.5 PDP-8

- Added instruction history.
- Added TSC8-75 option support for ETOS.
- Added TD8E DECtape support.

1.6 PDP-18b

- Added instruction history.
- Changed PDP-9, PDP-15 API default to enabled.

1.7 PDP-11

- Added support for 18b only Qbus devices.
- Formalized bus and addressing definitions.
- Added control to enable/disable autoconfiguration.
- Added stub support for second Unibus Ethernet controller.

1.7 Interdata 32b

- Added instruction history.

1.8 Eclipse

- Added floating point support.
- Added programmable interval timer support.

1.9 H316

- Added DMA/DMC support.
- Added fixed head disk support.
- Added moving head disk support.
- Added magtape support.

1.10 IBM 1130 (Brian Knittel)

- Added support for physical card reader, using the Cardread
interface (www.ibm1130.org/sim/downloads).
- Added support for physical printer (flushes output buffer after
each line).

2. Bugs Fixed in 3.1-0

2.1 SCP and libraries

- Fixed numerous bugs in Ethernet library.

2.2 All DECtapes

- Fixed reverse checksum value in 'read all' mode.
- Simplified (and sped up) timing.

2.3 PDP-8

- Fixed bug in RX28 read status (found by Charles Dickman).
- Fixed RX28 double density write.

2.4 PDP-18b

- Fixed autoincrement bug in PDP-4, PDP-7, PDP-9.

2.5 PDP-11/VAX

- Revised RQ MB->LBN conversion for greater accuracy.
- Fixed bug in IO configuration (found by David Hittner).
- Fixed bug with multiple RQ RAUSER drives.
- Fixed bug in second Qbus Ethernet controller interrupts.

2.6 Nova/Eclipse

- Fixed bugs in DKP flag clear, map setup, map usage (Charles Owen).
- Fixed bug in MT, reset completes despite I/O reset (Charles Owen).
- Fixed bug in MT, space operations return word count (Charles Owen).

2.7 IBM 1130 (Brian Knittel)

- Fixed bug in setting carry bit in subtract and subtract double.
- Fixed timing problem in console printer simulation.

2.8 1620

- Fixed bug in branch digit (found by Dave Babcock).

3. New Features in 3.0 vs prior releases

3.1 SCP and Libraries

- Added ASSIGN/DEASSIGN (logical name) commands.
- Changed RESTORE to unconditionally detach files.
- Added E11 and TPC format support to magtape library.
- Fixed bug in SHOW CONNECTIONS.
- Added USE_ADDR64 support.

3.2 All magtapes

- Magtapes support SIMH format, E11 format, and TPC format (read only).
- SET <tape_unit> FORMAT=format sets the specified tape unit's format.
- SHOW <tape_unit> FORMAT displays the specified tape unit's format.
- Tape format can also be set as part of the ATTACH command, using
  the -F switch.

3.3 VAX

- VAX can be compiled without USE_INT64.
- If compiled with USE_INT64 and USE_ADDR64, RQ and TQ controllers support
  files > 2GB.
- VAX ROM has speed control (SET ROM DELAY/NODELAY).

3.4 PDP-1

- Added block loader format support to LOAD.
- Changed BOOT PTR to allow loading of all of the first bank of memory.
- The LOAD command takes an optional argument specifying the memory field
  to be loaded.
- The PTR BOOT command takes its starting memory field from the TA (address
  switch) register.

3.5 PDP-18b Family

- Added PDP-4 EAE support.
- Added PDP-15 FP15 support.
- Added PDP-15 XVM support.
- Added PDP-15 "re-entrancy ECO".
- Added PDP-7, PDP-9, PDP-15 hardware RIM loader support in BOOT PTR.

4. Bugs Fixed in 3.0 vs prior releases

4.1 SCP and Libraries

- Fixed end of file problem in dep, idep.
- Fixed handling of trailing spaces in dep, idep.

4.2 VAX

- Fixed CVTfi bug: integer overflow not set if exponent out of range
- Fixed EMODx bugs:
  o First and second operands reversed
  o Separated fraction received wrong exponent
  o Overflow calculation on separated integer incorrect
  o Fraction not set to zero if exponent out of range
- Fixed interval timer and ROM access to pass power-up self-test even on very
  fast host processors (fixes from Mark Pizzolato).
- Fixed bug in user disk size (found by Chaskiel M Grundman).

4.3 1401

- Fixed mnemonic, instruction lengths, and reverse scan length check bug for MCS.
- Fixed MCE bug, BS off by 1 if zero suppress.
- Fixed chaining bug, D lost if return to SCP.
- Fixed H branch, branch occurs after continue.
- Added check for invalid 8 character MCW, LCA.
- Fixed magtape load-mode end of record response.
- Revised fetch to model hardware more closely.
- Fixed tape read end-of-record handling based on real 1401.
- Added diagnostic read (space forward).

4.4 Nova

- Fixed DSK variable size interaction with restore.
- Fixed bug in DSK set size routine.

4.5 PDP-1

- Fixed DT variable size interaction with restore.
- Updated CPU, line printer, standard devices to detect indefinite I/O wait.
- Fixed incorrect logical, missing activate, break in drum simulator.
- Fixed bugs in instruction decoding, overprinting for line printer.
- Fixed system hang if continue after PTR error.
- Fixed PTR to start/stop on successive rpa instructions.

4.6 PDP-11

- Fixed DT variable size interaction with restore.
- Fixed bug in MMR1 update (found by Tim Stark).
- Added XQ features and fixed bugs:
  o Corrected XQ interrupts on IE state transition (code by Tom Evans).
  o Added XQ interrupt clear on soft reset.
  o Removed XQ interrupt when setting XL or RL (multiple people).
  o Added SET/SHOW XQ STATS.
  o Added SHOW XQ FILTERS.
  o Added ability to split received packet into multiple buffers.
  o Added explicit runt and giant packet processing.
- Fixed bug in user disk size (found by Chaskiel M Grundman).

4.7 PDP-18B

- Fixed DT, RF variable size interaction with restore.
- Fixed MT bug in MTTR.
- Fixed bug in PDP-4 line printer overprinting.
- Fixed bug in PDP-15 memory protect/skip interaction.
- Fixed bug in RF set size routine.
- Increased PTP TIME for PDP-15 operating systems.
- Fixed priorities in PDP-15 API (differs from PDP-9).
- Fixed sign handling in PDP-15 EAE unsigned mul/div (differs from PDP-9).
- Fixed bug in CAF, clears API subsystem.

4.8 PDP-8

- Fixed DT, DF, RF, RX variable size interaction with restore.
- Fixed MT bug in SKTR.
- Fixed bug in DF, RF set size routine.

4.9 HP2100

- Fixed bug in DP (13210A controller only), DQ read status.
- Fixed bug in DP, DQ seek complete.
- Fixed DR drum sizes.
- Fixed DR variable capacity interaction with SAVE/RESTORE.

4.10 GRI

- Fixed bug in SC queue pointer management.

4.11 PDP-10

- Fixed bug in RP read header.

4.12 Ibm1130

- Fixed bugs found by APL 1130.

4.13 Altairz80

- Fixed bug in real-time clock on Windows host.

4.14 1620

- Fixed bug in immediate index add (found by Michael Short).
2011-04-15 08:34:20 -07:00

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/* hp2100_dr.c: HP 2100 12606B/12610B fixed head disk/drum simulator
Copyright (c) 1993-2003, 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.
fhd 12606B 2770/2771 fixed head disk
12610B 2773/2774/2775 drum
These head-per-track devices are buffered in memory, to minimize overhead.
The drum data channel does not have a command flip-flop. Its control
flip-flop is not wired into the interrupt chain; accordingly, the
simulator uses command rather than control for the data channel. Its
flag does not respond to SFS, SFC, or STF.
The drum control channel does not have any of the traditional flip-flops.
27-Jul-03 RMS Fixed drum sizes
Fixed variable capacity interaction with SAVE/RESTORE
10-Nov-02 RMS Added BOOT command
*/
#include "hp2100_defs.h"
#include <math.h>
/* Constants */
#define DR_NUMWD 64 /* words/sector */
#define DR_FNUMSC 90 /* fhd sec/track */
#define DR_DNUMSC 32 /* drum sec/track */
#define DR_NUMSC ((drc_unit.flags & UNIT_DR)? DR_DNUMSC: DR_FNUMSC)
#define DR_SIZE (512 * DR_DNUMSC * DR_NUMWD) /* initial size */
#define UNIT_V_SZ (UNIT_V_UF) /* disk vs drum */
#define UNIT_M_SZ 017 /* size */
#define UNIT_SZ (UNIT_M_SZ << UNIT_V_SZ)
#define UNIT_DR (1 << UNIT_V_SZ) /* low order bit */
#define SZ_180K 000 /* disks */
#define SZ_360K 002
#define SZ_720K 004
#define SZ_1024K 001 /* drums: default size */
#define SZ_1536K 003
#define SZ_384K 005
#define SZ_512K 007
#define SZ_640K 011
#define SZ_768K 013
#define SZ_896K 015
#define DR_GETSZ(x) (((x) >> UNIT_V_SZ) & UNIT_M_SZ)
/* Command word */
#define CW_WR 0100000 /* write vs read */
#define CW_V_FTRK 7 /* fhd track */
#define CW_M_FTRK 0177
#define CW_V_DTRK 5 /* drum track */
#define CW_M_DTRK 01777
#define MAX_TRK (((drc_unit.flags & UNIT_DR)? CW_M_DTRK: CW_M_FTRK) + 1)
#define CW_GETTRK(x) ((drc_unit.flags & UNIT_DR)? \
(((x) >> CW_V_DTRK) & CW_M_DTRK): \
(((x) >> CW_V_FTRK) & CW_M_FTRK))
#define CW_PUTTRK(x) ((drc_unit.flags & UNIT_DR)? \
(((x) & CW_M_DTRK) << CW_V_DTRK): \
(((x) & CW_M_FTRK) << CW_V_FTRK))
#define CW_V_FSEC 0 /* fhd sector */
#define CW_M_FSEC 0177
#define CW_V_DSEC 0 /* drum sector */
#define CW_M_DSEC 037
#define CW_GETSEC(x) ((drc_unit.flags & UNIT_DR)? \
(((x) >> CW_V_DSEC) & CW_M_DSEC): \
(((x) >> CW_V_FSEC) & CW_M_FSEC))
#define CW_PUTSEC(x) ((drc_unit.flags & UNIT_DR)? \
(((x) & CW_M_DSEC) << CW_V_DSEC): \
(((x) & CW_M_FSEC) << CW_V_FSEC))
/* Status register */
#define DRS_V_NS 8 /* next sector */
#define DRS_M_NS 0177
#define DRS_SEC 0100000 /* sector flag */
#define DRS_RDY 0000200 /* ready */
#define DRS_RIF 0000100 /* read inhibit */
#define DRS_SAC 0000040 /* sector coincidence */
#define DRS_ABO 0000010 /* abort */
#define DRS_WEN 0000004 /* write enabled */
#define DRS_PER 0000002 /* parity error */
#define DRS_BSY 0000001 /* busy */
#define GET_CURSEC(x) ((int32) fmod (sim_gtime() / ((double) (x)), \
((double) ((drc_unit.flags & UNIT_DR)? DR_DNUMSC: DR_FNUMSC))))
extern UNIT cpu_unit;
extern uint16 *M;
extern uint32 PC;
extern uint32 dev_cmd[2], dev_ctl[2], dev_flg[2], dev_fbf[2];
int32 drc_cw = 0; /* fnc, addr */
int32 drc_sta = 0; /* status */
int32 drd_ibuf = 0; /* input buffer */
int32 drd_obuf = 0; /* output buffer */
int32 drd_ptr = 0; /* sector pointer */
int32 dr_stopioe = 1; /* stop on error */
int32 dr_time = 10; /* time per word */
static int32 sz_tab[16] = {
184320, 1048576, 368640, 1572864, 737280, 393216, 0, 524288,
0, 655360, 0, 786432, 0, 917504, 0, 0 };
DEVICE drd_dev, drc_dev;
int32 drdio (int32 inst, int32 IR, int32 dat);
int32 drcio (int32 inst, int32 IR, int32 dat);
t_stat drc_svc (UNIT *uptr);
t_stat drc_reset (DEVICE *dptr);
t_stat drc_attach (UNIT *uptr, char *cptr);
t_stat drc_boot (int32 unitno, DEVICE *dptr);
int32 dr_incda (int32 trk, int32 sec, int32 ptr);
t_stat dr_set_size (UNIT *uptr, int32 val, char *cptr, void *desc);
/* DRD data structures
drd_dev device descriptor
drd_unit unit descriptor
drd_reg register list
*/
DIB dr_dib[] = {
{ DRD, 0, 0, 0, 0, &drdio },
{ DRC, 0, 0, 0, 0, &drcio } };
#define drd_dib dr_dib[0]
#define drc_dib dr_dib[1]
UNIT drd_unit = { UDATA (NULL, 0, 0) };
REG drd_reg[] = {
{ ORDATA (IBUF, drd_ibuf, 16) },
{ ORDATA (OBUF, drd_obuf, 16) },
{ FLDATA (CMD, drd_dib.cmd, 0) },
{ FLDATA (CTL, drd_dib.ctl, 0) },
{ FLDATA (FLG, drd_dib.flg, 0) },
{ FLDATA (FBF, drd_dib.fbf, 0) },
{ ORDATA (BPTR, drd_ptr, 6) },
{ ORDATA (DEVNO, drd_dib.devno, 6), REG_HRO },
{ NULL } };
MTAB drd_mod[] = {
{ MTAB_XTD | MTAB_VDV, 1, "DEVNO", "DEVNO",
&hp_setdev, &hp_showdev, &drd_dev },
{ 0 } };
DEVICE drd_dev = {
"DRD", &drd_unit, drd_reg, drd_mod,
1, 0, 0, 0, 0, 0,
NULL, NULL, NULL,
NULL, NULL, NULL,
&drd_dib, DEV_DISABLE };
/* DRC data structures
drc_dev device descriptor
drc_unit unit descriptor
drc_mod unit modifiers
drc_reg register list
*/
UNIT drc_unit =
{ UDATA (&drc_svc, UNIT_FIX+UNIT_ATTABLE+UNIT_BUFABLE+
UNIT_MUSTBUF+UNIT_DR+UNIT_BINK, DR_SIZE) };
REG drc_reg[] = {
{ ORDATA (CW, drc_cw, 16) },
{ ORDATA (STA, drc_sta, 16) },
{ FLDATA (CMD, drc_dib.cmd, 0) },
{ FLDATA (CTL, drc_dib.ctl, 0) },
{ FLDATA (FLG, drc_dib.flg, 0) },
{ FLDATA (FBF, drc_dib.fbf, 0) },
{ DRDATA (TIME, dr_time, 24), REG_NZ + PV_LEFT },
{ FLDATA (STOP_IOE, dr_stopioe, 0) },
{ ORDATA (DEVNO, drc_dib.devno, 6), REG_HRO },
{ DRDATA (CAPAC, drc_unit.capac, 24), REG_HRO },
{ NULL } };
MTAB drc_mod[] = {
{ UNIT_DR, 0, "disk", NULL, NULL },
{ UNIT_DR, UNIT_DR, "drum", NULL, NULL },
{ UNIT_SZ, (SZ_180K << UNIT_V_SZ), NULL, "180K", &dr_set_size },
{ UNIT_SZ, (SZ_360K << UNIT_V_SZ), NULL, "360K", &dr_set_size },
{ UNIT_SZ, (SZ_720K << UNIT_V_SZ), NULL, "720K", &dr_set_size },
{ UNIT_SZ, (SZ_384K << UNIT_V_SZ), NULL, "384K", &dr_set_size },
{ UNIT_SZ, (SZ_512K << UNIT_V_SZ), NULL, "512K", &dr_set_size },
{ UNIT_SZ, (SZ_640K << UNIT_V_SZ), NULL, "640K", &dr_set_size },
{ UNIT_SZ, (SZ_768K << UNIT_V_SZ), NULL, "768K", &dr_set_size },
{ UNIT_SZ, (SZ_896K << UNIT_V_SZ), NULL, "896K", &dr_set_size },
{ UNIT_SZ, (SZ_1024K << UNIT_V_SZ), NULL, "1024K", &dr_set_size },
{ UNIT_SZ, (SZ_1536K << UNIT_V_SZ), NULL, "1536K", &dr_set_size },
{ MTAB_XTD | MTAB_VDV, 1, "DEVNO", "DEVNO",
&hp_setdev, &hp_showdev, &drd_dev },
{ 0 } };
DEVICE drc_dev = {
"DRC", &drc_unit, drc_reg, drc_mod,
1, 8, 21, 1, 8, 16,
NULL, NULL, &drc_reset,
&drc_boot, &drc_attach, NULL,
&drc_dib, DEV_DISABLE };
/* IOT routines */
int32 drdio (int32 inst, int32 IR, int32 dat)
{
int32 devd, t;
devd = IR & I_DEVMASK; /* get device no */
switch (inst) { /* case on opcode */
case ioOTX: /* output */
drd_obuf = dat;
break;
case ioMIX: /* merge */
dat = dat | drd_ibuf;
break;
case ioLIX: /* load */
dat = drd_ibuf;
break;
case ioCTL: /* control clear/set */
if (IR & I_AB) { /* CLC */
clrCMD (devd); /* clr "ctl" */
clrFLG (devd); /* clr flg */
drc_sta = drc_sta & ~DRS_SAC; } /* clear SAC flag */
else if (!CMD (devd)) { /* STC, not set? */
setCMD (devd); /* set "ctl" */
if (drc_cw & CW_WR) { setFLG (devd); } /* prime DMA */
drc_sta = 0; /* clear errors */
drd_ptr = 0; /* clear sec ptr */
sim_cancel (&drc_unit); /* cancel curr op */
t = CW_GETSEC (drc_cw) - GET_CURSEC (dr_time * DR_NUMWD);
if (t <= 0) t = t + DR_NUMSC;
sim_activate (&drc_unit, t * DR_NUMWD * dr_time); }
break;
default:
break; }
if (IR & I_HC) { clrFLG (devd); } /* H/C option */
return dat;
}
int32 drcio (int32 inst, int32 IR, int32 dat)
{
int32 st;
switch (inst) { /* case on opcode */
case ioSFC: /* skip flag clear */
PC = (PC + 1) & VAMASK;
return dat;
case ioOTX: /* output */
drc_cw = dat;
break;
case ioLIX: /* load */
dat = 0;
case ioMIX: /* merge */
if (drc_unit.flags & UNIT_ATT) /* attached? */
st = GET_CURSEC (dr_time) | DRS_RDY | drc_sta |
(sim_is_active (&drc_unit)? DRS_BSY: 0);
else st = drc_sta;
dat = dat | st; /* merge status */
break;
default:
break; }
return dat;
}
/* Unit service */
t_stat drc_svc (UNIT *uptr)
{
int32 devd, trk, sec;
uint32 da;
uint16 *bptr = uptr->filebuf;
if ((uptr->flags & UNIT_ATT) == 0) {
drc_sta = DRS_ABO;
return IORETURN (dr_stopioe, SCPE_UNATT); }
drc_sta = drc_sta | DRS_SAC;
devd = drd_dib.devno; /* get dch devno */
trk = CW_GETTRK (drc_cw);
sec = CW_GETSEC (drc_cw);
da = ((trk * DR_NUMSC) + sec) * DR_NUMWD;
if (drc_cw & CW_WR) { /* write? */
if ((da < uptr->capac) && (sec < DR_NUMSC)) {
bptr[da + drd_ptr] = drd_obuf;
if (((uint32) (da + drd_ptr)) >= uptr->hwmark)
uptr->hwmark = da + drd_ptr + 1; }
drd_ptr = dr_incda (trk, sec, drd_ptr); /* inc disk addr */
if (CMD (devd)) { /* dch active? */
setFLG (devd); /* set dch flg */
sim_activate (uptr, dr_time); } /* sched next word */
else if (drd_ptr) { /* done, need to fill? */
for ( ; drd_ptr < DR_NUMWD; drd_ptr++)
bptr[da + drd_ptr] = 0; }
} /* end write */
else { /* read */
if (CMD (devd)) { /* dch active? */
if ((da >= uptr->capac) || (sec >= DR_NUMSC)) drd_ibuf = 0;
else drd_ibuf = bptr[da + drd_ptr];
drd_ptr = dr_incda (trk, sec, drd_ptr);
setFLG (devd); /* set dch flg */
sim_activate (uptr, dr_time); } /* sched next word */
}
return SCPE_OK;
}
/* Increment current disk address */
int32 dr_incda (int32 trk, int32 sec, int32 ptr)
{
ptr = ptr + 1; /* inc pointer */
if (ptr >= DR_NUMWD) { /* end sector? */
ptr = 0; /* new sector */
sec = sec + 1; /* adv sector */
if (sec >= DR_NUMSC) { /* end track? */
sec = 0; /* new track */
trk = trk + 1; /* adv track */
if (trk >= MAX_TRK) trk = 0; } /* wraps at max */
drc_cw = (drc_cw & CW_WR) | CW_PUTTRK (trk) | CW_PUTSEC (sec);
}
return ptr;
}
/* Reset routine */
t_stat drc_reset (DEVICE *dptr)
{
hp_enbdis_pair (&drc_dev, &drd_dev); /* make pair cons */
drc_sta = drc_cw = drd_ptr = 0;
drc_dib.cmd = drd_dib.cmd = 0; /* clear cmd */
drc_dib.ctl = drd_dib.ctl = 0; /* clear ctl */
drc_dib.fbf = drd_dib.fbf = 0; /* clear fbf */
drc_dib.flg = drd_dib.flg = 0; /* clear flg */
sim_cancel (&drc_unit);
return SCPE_OK;
}
/* Attach routine */
t_stat drc_attach (UNIT *uptr, char *cptr)
{
int32 sz = sz_tab[DR_GETSZ (uptr->flags)];
if (sz == 0) return SCPE_IERR;
uptr->capac = sz;
return attach_unit (uptr, cptr);
}
/* Set size routine */
t_stat dr_set_size (UNIT *uptr, int32 val, char *cptr, void *desc)
{
int32 sz;
if (val < 0) return SCPE_IERR;
if ((sz = sz_tab[DR_GETSZ (val)]) == 0) return SCPE_IERR;
if (uptr->flags & UNIT_ATT) return SCPE_ALATT;
uptr->capac = sz;
return SCPE_OK;
}
/* Fixed head disk/drum bootstrap routine (disc subset of disc/paper tape loader) */
#define CHANGE_DEV (1 << 24)
#define BOOT_BASE 056
#define BOOT_START 060
static const int32 dboot[IBL_LNT - BOOT_BASE] = {
0020000+CHANGE_DEV, /*DMA 20000+DC */
0000000, /* 0 */
0107700, /* CLC 0,C */
0063756, /* LDA DMA ; DMA ctrl */
0102606, /* OTA 6 */
0002700, /* CLA,CCE */
0102601+CHANGE_DEV, /* OTA CC ; trk = sec = 0 */
0001500, /* ERA ; A = 100000 */
0102602, /* OTA 2 ; DMA in, addr */
0063777, /* LDA M64 */
0102702, /* STC 2 */
0102602, /* OTA 2 ; DMA wc = -64 */
0103706, /* STC 6,C ; start DMA */
0067776, /* LDB JSF ; get JMP . */
0074077, /* STB 77 ; in base page */
0102700+CHANGE_DEV, /* STC DC ; start disc */
0024077, /*JSF JMP 77 ; go wait */
0177700 }; /*M64 -100 */
t_stat drc_boot (int32 unitno, DEVICE *dptr)
{
int32 i, dev, ad;
if (unitno != 0) return SCPE_NOFNC; /* only unit 0 */
dev = drd_dib.devno; /* get data chan dev */
ad = ((MEMSIZE - 1) & ~IBL_MASK) & VAMASK; /* start at mem top */
for (i = 0; i < (IBL_LNT - BOOT_BASE); i++) { /* copy bootstrap */
if (dboot[i] & CHANGE_DEV) /* IO instr? */
M[ad + BOOT_BASE + i] = (dboot[i] + dev) & DMASK;
else M[ad + BOOT_BASE + i] = dboot[i]; }
PC = ad + BOOT_START;
return SCPE_OK;
}