1 /*************************************************************************
2  *                                                                       *
3  * $Id: s100_disk2.c 1995 2008-07-15 03:59:13Z hharte $                  *
4  *                                                                       *
5  * Copyright (c) 2007-2008 Howard M. Harte.                              *
6  * http://www.hartetec.com                                               *
7  *                                                                       *
8  * Permission is hereby granted, free of charge, to any person obtaining *
9  * a copy of this software and associated documentation files (the       *
10  * "Software"), to deal in the Software without restriction, including   *
11  * without limitation the rights to use, copy, modify, merge, publish,   *
12  * distribute, sublicense, and/or sell copies of the Software, and to    *
13  * permit persons to whom the Software is furnished to do so, subject to *
14  * the following conditions:                                             *
15  *                                                                       *
16  * The above copyright notice and this permission notice shall be        *
17  * included in all copies or substantial portions of the Software.       *
18  *                                                                       *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       *
20  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    *
21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND                 *
22  * NONINFRINGEMENT. IN NO EVENT SHALL HOWARD M. HARTE BE LIABLE FOR ANY  *
23  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  *
24  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     *
25  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                *
26  *                                                                       *
27  * Except as contained in this notice, the name of Howard M. Harte shall *
28  * not be used in advertising or otherwise to promote the sale, use or   *
29  * other dealings in this Software without prior written authorization   *
30  * Howard M. Harte.                                                      *
31  *                                                                       *
32  * SIMH Interface based on altairz80_hdsk.c, by Peter Schorn.            *
33  *                                                                       *
34  * Module Description:                                                   *
35  *     CompuPro DISK2 Hard Disk Controller module for SIMH.              *
36  * This module must be used in conjunction with the CompuPro Selector    *
37  * Channel Module for proper operation.                                  *
38  *                                                                       *
39  * Environment:                                                          *
40  *     User mode only                                                    *
41  *                                                                       *
42  *************************************************************************/
43 
44 #include "altairz80_defs.h"
45 
46 #if defined (_WIN32)
47 #include <windows.h>
48 #endif
49 
50 #include "sim_imd.h"
51 
52 /* Debug flags */
53 #define ERROR_MSG   (1 << 0)
54 #define SEEK_MSG    (1 << 1)
55 #define CMD_MSG     (1 << 2)
56 #define RD_DATA_MSG (1 << 3)
57 #define WR_DATA_MSG (1 << 4)
58 #define STATUS_MSG  (1 << 5)
59 #define IRQ_MSG     (1 << 6)
60 #define VERBOSE_MSG (1 << 7)
61 
62 #define DISK2_MAX_DRIVES    4
63 
64 typedef union {
65     uint8 raw[2051];
66     struct {
67         uint8 header[3];
68         uint8 data[2048];
69     } u;
70 } SECTOR_FORMAT;
71 
72 static SECTOR_FORMAT sdata;
73 
74 typedef struct {
75     UNIT *uptr;
76     DISK_INFO *imd;
77     uint16 ntracks;  /* number of tracks */
78     uint8 nheads;    /* number of heads */
79     uint8 nsectors;  /* number of sectors/track */
80     uint32 sectsize; /* sector size, not including pre/postamble */
81     uint16 track;    /* Current Track */
82     uint8 ready;     /* Is drive ready? */
83 } DISK2_DRIVE_INFO;
84 
85 typedef struct {
86     PNP_INFO    pnp;    /* Plug and Play */
87     uint8   sel_drive;  /* Currently selected drive */
88     uint8   head_sel;   /* Head select (signals to drive itself) */
89     uint8   head;       /* Head set by write to the HEAD register */
90     uint8   cyl;        /* Cyl that the current operation is targetting */
91     uint8   sector;     /* Sector the current READ/WRITE operation is targetting */
92     uint8   hdr_sector; /* Current sector for WRITE_HEADER */
93     uint8   ctl_attn;
94     uint8   ctl_run;
95     uint8   ctl_op;
96     uint8   ctl_fault_clr;
97     uint8   ctl_us;
98     uint8   timeout;
99     uint8   crc_error;
100     uint8   overrun;
101     uint8   seek_complete;
102     uint8   write_fault;
103     DISK2_DRIVE_INFO drive[DISK2_MAX_DRIVES];
104 } DISK2_INFO;
105 
106 static DISK2_INFO disk2_info_data = { { 0x0, 0, 0xC8, 2 } };
107 static DISK2_INFO *disk2_info = &disk2_info_data;
108 
109 /* Default geometry for a 20MB hard disk. */
110 #define C20MB_NTRACKS   243
111 #define C20MB_NHEADS    8
112 #define C20MB_NSECTORS  11
113 #define C20MB_SECTSIZE  1024
114 
115 static int32 ntracks      = C20MB_NTRACKS;
116 static int32 nheads       = C20MB_NHEADS;
117 static int32 nsectors     = C20MB_NSECTORS;
118 static int32 sectsize     = C20MB_SECTSIZE;
119 
120 extern uint32 PCX;
121 extern REG *sim_PC;
122 extern t_stat set_iobase(UNIT *uptr, int32 val, char *cptr, void *desc);
123 extern t_stat show_iobase(FILE *st, UNIT *uptr, int32 val, void *desc);
124 extern uint32 sim_map_resource(uint32 baseaddr, uint32 size, uint32 resource_type,
125         int32 (*routine)(const int32, const int32, const int32), uint8 unmap);
126 extern int32 selchan_dma(uint8 *buf, uint32 len);
127 extern int32 find_unit_index(UNIT *uptr);
128 extern void raise_ss1_interrupt(uint8 intnum);
129 
130 #define UNIT_V_DISK2_WLK        (UNIT_V_UF + 0) /* write locked                             */
131 #define UNIT_DISK2_WLK          (1 << UNIT_V_DISK2_WLK)
132 #define UNIT_V_DISK2_VERBOSE    (UNIT_V_UF + 1) /* verbose mode, i.e. show error messages   */
133 #define UNIT_DISK2_VERBOSE      (1 << UNIT_V_DISK2_VERBOSE)
134 #define DISK2_CAPACITY          (C20MB_NTRACKS*C20MB_NHEADS*C20MB_NSECTORS*C20MB_SECTSIZE)   /* Default Disk Capacity */
135 
136 static t_stat disk2_reset(DEVICE *disk2_dev);
137 static t_stat disk2_attach(UNIT *uptr, char *cptr);
138 static t_stat disk2_detach(UNIT *uptr);
139 static void raise_disk2_interrupt(void);
140 
141 static int32 disk2dev(const int32 port, const int32 io, const int32 data);
142 
143 static uint8 DISK2_Read(const uint32 Addr);
144 static uint8 DISK2_Write(const uint32 Addr, uint8 cData);
145 
146 static UNIT disk2_unit[] = {
147     { UDATA (NULL, UNIT_FIX + UNIT_ATTABLE + UNIT_DISABLE + UNIT_ROABLE, DISK2_CAPACITY) },
148     { UDATA (NULL, UNIT_FIX + UNIT_ATTABLE + UNIT_DISABLE + UNIT_ROABLE, DISK2_CAPACITY) },
149     { UDATA (NULL, UNIT_FIX + UNIT_ATTABLE + UNIT_DISABLE + UNIT_ROABLE, DISK2_CAPACITY) },
150     { UDATA (NULL, UNIT_FIX + UNIT_ATTABLE + UNIT_DISABLE + UNIT_ROABLE, DISK2_CAPACITY) }
151 };
152 
153 static REG disk2_reg[] = {
154     { DRDATA (NTRACKS,    ntracks,             10), },
155     { DRDATA (NHEADS,     nheads,              8), },
156     { DRDATA (NSECTORS,   nsectors,            8), },
157     { DRDATA (SECTSIZE,   sectsize,            11), },
158     { HRDATA (SEL_DRIVE,  disk2_info_data.sel_drive, 3), },
159     { HRDATA (CYL,        disk2_info_data.cyl,       8), },
160     { HRDATA (HEAD,       disk2_info_data.head,      8), },
161     { HRDATA (SECTOR,     disk2_info_data.sector,    8), },
162 
163     { NULL }
164 };
165 
166 static MTAB disk2_mod[] = {
167     { MTAB_XTD|MTAB_VDV,    0,                  "IOBASE",   "IOBASE",   &set_iobase, &show_iobase, NULL },
168     { UNIT_DISK2_WLK,       0,                  "WRTENB",   "WRTENB",   NULL  },
169     { UNIT_DISK2_WLK,       UNIT_DISK2_WLK,     "WRTLCK",   "WRTLCK",   NULL  },
170     /* quiet, no warning messages       */
171     { UNIT_DISK2_VERBOSE,   0,                  "QUIET",    "QUIET",    NULL   },
172     /* verbose, show warning messages   */
173     { UNIT_DISK2_VERBOSE,   UNIT_DISK2_VERBOSE, "VERBOSE",  "VERBOSE",  NULL },
174     { 0 }
175 };
176 
177 /* Debug Flags */
178 static DEBTAB disk2_dt[] = {
179     { "ERROR",  ERROR_MSG },
180     { "SEEK",   SEEK_MSG },
181     { "CMD",    CMD_MSG },
182     { "RDDATA", RD_DATA_MSG },
183     { "WRDATA", WR_DATA_MSG },
184     { "STATUS", STATUS_MSG },
185     { "IRQ",    IRQ_MSG },
186     { "VERBOSE",VERBOSE_MSG },
187     { NULL,     0 }
188 };
189 
190 DEVICE disk2_dev = {
191     "DISK2", disk2_unit, disk2_reg, disk2_mod,
192     DISK2_MAX_DRIVES, 10, 31, 1, DISK2_MAX_DRIVES, DISK2_MAX_DRIVES,
193     NULL, NULL, &disk2_reset,
194     NULL, &disk2_attach, &disk2_detach,
195     &disk2_info_data, (DEV_DISABLE | DEV_DIS | DEV_DEBUG), ERROR_MSG,
196     disk2_dt, NULL, "Compupro Hard Disk Controller DISK2"
197 };
198 
199 /* Reset routine */
disk2_reset(DEVICE * dptr)200 static t_stat disk2_reset(DEVICE *dptr)
201 {
202     PNP_INFO *pnp = (PNP_INFO *)dptr->ctxt;
203 
204     if(dptr->flags & DEV_DIS) { /* Disconnect I/O Ports */
205         sim_map_resource(pnp->io_base, pnp->io_size, RESOURCE_TYPE_IO, &disk2dev, TRUE);
206     } else {
207         /* Connect DISK2 at base address */
208         if(sim_map_resource(pnp->io_base, pnp->io_size, RESOURCE_TYPE_IO, &disk2dev, FALSE) != 0) {
209             printf("%s: error mapping I/O resource at 0x%04x\n", __FUNCTION__, pnp->io_base);
210             return SCPE_ARG;
211         }
212     }
213     return SCPE_OK;
214 }
215 
216 
217 /* Attach routine */
disk2_attach(UNIT * uptr,char * cptr)218 static t_stat disk2_attach(UNIT *uptr, char *cptr)
219 {
220     t_stat r = SCPE_OK;
221     DISK2_DRIVE_INFO *pDrive;
222     int i = 0;
223 
224     i = find_unit_index(uptr);
225     if (i == -1) {
226         return (SCPE_IERR);
227     }
228     pDrive = &disk2_info->drive[i];
229 
230     pDrive->ready = 1;
231     disk2_info->write_fault = 1;
232     pDrive->track = 5;
233     pDrive->ntracks = ntracks;
234     pDrive->nheads = nheads;
235     pDrive->nsectors = nsectors;
236     pDrive->sectsize = sectsize;
237 
238     r = attach_unit(uptr, cptr);    /* attach unit  */
239     if ( r != SCPE_OK)              /* error?       */
240         return r;
241 
242     /* Determine length of this disk */
243     if(sim_fsize(uptr->fileref) != 0) {
244         uptr->capac = sim_fsize(uptr->fileref);
245     } else {
246         uptr->capac = (pDrive->ntracks * pDrive->nsectors * pDrive->nheads * pDrive->sectsize);
247     }
248 
249     pDrive->uptr = uptr;
250 
251     /* Default for new file is DSK */
252     uptr->u3 = IMAGE_TYPE_DSK;
253 
254     if(uptr->capac > 0) {
255         r = assignDiskType(uptr);
256         if (r != SCPE_OK) {
257             disk2_detach(uptr);
258             return r;
259         }
260     }
261 
262     if (uptr->flags & UNIT_DISK2_VERBOSE)
263         printf("DISK2%d, attached to '%s', type=%s, len=%d\n", i, cptr,
264             uptr->u3 == IMAGE_TYPE_IMD ? "IMD" : uptr->u3 == IMAGE_TYPE_CPT ? "CPT" : "DSK",
265             uptr->capac);
266 
267     if(uptr->u3 == IMAGE_TYPE_IMD) {
268         if(uptr->capac < 318000) {
269             printf("Cannot create IMD files with SIMH.\nCopy an existing file and format it with CP/M.\n");
270             disk2_detach(uptr);
271             return SCPE_OPENERR;
272         }
273 
274         if (uptr->flags & UNIT_DISK2_VERBOSE)
275             printf("--------------------------------------------------------\n");
276         disk2_info->drive[i].imd = diskOpen((uptr->fileref), (uptr->flags & UNIT_DISK2_VERBOSE));
277         if (uptr->flags & UNIT_DISK2_VERBOSE)
278             printf("\n");
279     } else {
280         disk2_info->drive[i].imd = NULL;
281     }
282 
283     return SCPE_OK;
284 }
285 
286 
287 /* Detach routine */
disk2_detach(UNIT * uptr)288 t_stat disk2_detach(UNIT *uptr)
289 {
290     t_stat r;
291     int8 i;
292 
293     i = find_unit_index(uptr);
294 
295     if (i == -1) {
296         return (SCPE_IERR);
297     }
298 
299     if (uptr->flags & UNIT_DISK2_VERBOSE)
300         printf("Detach DISK2%d\n", i);
301 
302     r = detach_unit(uptr);  /* detach unit */
303     if ( r != SCPE_OK)
304         return r;
305 
306     return SCPE_OK;
307 }
308 
309 
disk2dev(const int32 port,const int32 io,const int32 data)310 static int32 disk2dev(const int32 port, const int32 io, const int32 data)
311 {
312 /*  sim_debug(VERBOSE_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT " IO %s, Port %02x\n", PCX, io ? "WR" : "RD", port); */
313     if(io) {
314         DISK2_Write(port, data);
315         return 0;
316     } else {
317         return(DISK2_Read(port));
318     }
319 }
320 
321 #define DISK2_CSR   0   /* R=DISK2 Status / W=DISK2 Control Register */
322 #define DISK2_DATA  1   /* R=Step Pulse / W=Write Data Register */
323 
DISK2_Read(const uint32 Addr)324 static uint8 DISK2_Read(const uint32 Addr)
325 {
326     uint8 cData;
327     DISK2_DRIVE_INFO *pDrive;
328 
329     pDrive = &disk2_info->drive[disk2_info->sel_drive];
330     cData = 0x00;
331 
332     switch(Addr & 0x1) {
333         case DISK2_CSR:
334             cData  = (disk2_info->ctl_attn) << 7;
335             cData |= (disk2_info->timeout) << 6;
336             cData |= (disk2_info->crc_error) << 5;
337             cData |= (disk2_info->overrun) << 4;
338             cData |= (pDrive->ready == 0) ? 0x08 : 0x00;
339             cData |= (disk2_info->seek_complete == 0) ? 0x04 : 0x00;
340             cData |= (disk2_info->write_fault) << 1;
341             cData |= ((pDrive->track != 0) || (disk2_info->seek_complete == 0)) ? 0x01 : 0x00;
342             sim_debug(STATUS_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
343                       " RD STATUS = 0x%02x\n", PCX, cData);
344 
345             disk2_info->seek_complete = 1;
346             break;
347         case DISK2_DATA:
348             if(disk2_info->ctl_op & 0x04) {
349                 if(pDrive->track < pDrive->ntracks) {
350                     pDrive->track ++;
351                 }
352             } else {
353                 if(pDrive->track > 0) {
354                     pDrive->track --;
355                 }
356             }
357             sim_debug(SEEK_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
358                       " Step %s, Track=%d\n", PCX,
359                       disk2_info->ctl_op & 0x04 ? "IN" : "OUT", pDrive->track);
360             disk2_info->seek_complete = 0;
361             cData = 0xFF;           /* Return High-Z data */
362             break;
363     }
364 
365     return (cData);
366 }
367 
368 #define DISK2_OP_DRIVE  0x00
369 #define DISK2_OP_CYL    0x01
370 #define DISK2_OP_HEAD   0x02
371 #define DISK2_OP_SECTOR 0x03
372 
373 #define DISK2_CMD_NULL          0x00
374 #define DISK2_CMD_READ_DATA     0x01
375 #define DISK2_CMD_WRITE_DATA    0x02
376 #define DISK2_CMD_WRITE_HEADER  0x03
377 #define DISK2_CMD_READ_HEADER   0x04
378 
DISK2_Write(const uint32 Addr,uint8 cData)379 static uint8 DISK2_Write(const uint32 Addr, uint8 cData)
380 {
381     uint32 track_offset;
382     uint8 result = 0;
383     uint8 i;
384     long file_offset;
385     DISK2_DRIVE_INFO *pDrive;
386     size_t rtn;
387 
388     pDrive = &disk2_info->drive[disk2_info->sel_drive];
389 
390     switch(Addr & 0x1) {
391         case DISK2_CSR:     /* Write CTL register */
392             disk2_info->ctl_attn = (cData & 0x80) >> 7;
393             disk2_info->ctl_run = (cData & 0x40) >> 6;
394             disk2_info->ctl_op = (cData & 0x38) >> 3;
395             disk2_info->ctl_fault_clr = (cData & 0x04) >> 2;
396             if(disk2_info->ctl_fault_clr == 1) {
397                 disk2_info->timeout = 0;
398             }
399             disk2_info->ctl_us = (cData & 0x03);
400             sim_debug(VERBOSE_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
401                       " ATTN*=%d, RUN=%d, OP=%d, FAULT_CLR=%d, US=%d\n",
402                       PCX, disk2_info->ctl_attn, disk2_info->ctl_run,
403                       disk2_info->ctl_op, disk2_info->ctl_fault_clr,
404                       disk2_info->ctl_us);
405 
406             /* FIXME: seek_complete = 1 is needed by CP/M, but why? Also, maybe related,
407              *        there appears to be a bug in the seeking logic.  For some reason, the
408              *        pDrive->track does not equal the disk2_info->cyl, when doing READ_DATA and
409              *        WRITE_DATA commands.  For this reason, disk2_info->cyl is used instead of
410              *        pDrive->track for these commands.  For READ_HEADER and WRITE_HEADER,
411              *        pDrive->track is used, because the DISK2 format program (DISK2.COM) does not
412              *        issue DISK2_OP_CYL.  The root cause of this anomaly needs to be determined,
413              *        because it is surely a bug in the logic somewhere.
414              */
415              /* pDrive->track may be different from disk2_info->cyl when a program such as DISK2.COM
416                 moves the position of the track without informing the CP/M BIOS which stores the
417                 current track for each drive. This appears to be an application program bug.
418             */
419             disk2_info->seek_complete = 1;
420 
421             if(disk2_info->ctl_run == 1) {
422                 disk2_info->timeout = 0;
423                 track_offset = disk2_info->cyl * pDrive->nheads * pDrive->nsectors * (pDrive->sectsize + 3);
424 
425                 switch(disk2_info->ctl_op) {
426                     case DISK2_CMD_NULL:
427                         sim_debug(CMD_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
428                                   " NULL Command\n", PCX);
429                         break;
430                     case DISK2_CMD_READ_DATA:
431                         sim_debug(RD_DATA_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
432                                   " READ_DATA: (C:%d/H:%d/S:%d)\n", PCX, disk2_info->cyl, disk2_info->head, disk2_info->sector);
433                         if(disk2_info->head_sel != disk2_info->head) {
434                             printf("DISK2: " ADDRESS_FORMAT
435                                    " READ_DATA: head_sel != head" NLP, PCX);
436                         }
437                         /* See FIXME above... that might be why this does not work properly... */
438                         if(disk2_info->cyl != pDrive->track) { /* problem, should not happen, see above */
439                             sim_debug(ERROR_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
440                                       " READ_DATA: cyl=%d, track=%d\n", PCX, disk2_info->cyl, pDrive->track);
441                             pDrive->track = disk2_info->cyl; /* update track */
442                         }
443                         sim_fseek((pDrive->uptr)->fileref, track_offset + (disk2_info->head_sel * pDrive->nsectors * (pDrive->sectsize + 3)), SEEK_SET);
444                         for(i=0;i<pDrive->nsectors;i++) {
445                             /* Read sector */
446                             rtn = sim_fread(sdata.raw, 1, (pDrive->sectsize + 3), (pDrive->uptr)->fileref);
447                             if (rtn != (size_t)(pDrive->sectsize + 3)) {
448                                 sim_debug(ERROR_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
449                                           " READ_DATA: sim_fread error.\n", PCX);
450                             }
451                             if(sdata.u.header[2] == disk2_info->sector) {
452                                 if(sdata.u.header[0] != disk2_info->cyl) { /*pDrive->track) { */
453                                     printf("DISK2: " ADDRESS_FORMAT
454                                            " READ_DATA Incorrect header: track" NLP, PCX);
455                                     disk2_info->timeout = 1;
456                                 }
457                                 if(sdata.u.header[1] != disk2_info->head) {
458                                     printf("DISK2: " ADDRESS_FORMAT
459                                            " READ_DATA Incorrect header: head" NLP, PCX);
460                                     disk2_info->timeout = 1;
461                                 }
462 
463                                 selchan_dma(sdata.u.data, pDrive->sectsize);
464                                 break;
465                             }
466                             if(i == pDrive->nsectors) {
467                                 printf("DISK2: " ADDRESS_FORMAT
468                                        " Sector not found" NLP, PCX);
469                                 disk2_info->timeout = 1;
470                             }
471                         }
472 
473                         break;
474                     case DISK2_CMD_WRITE_DATA:
475                         sim_debug(WR_DATA_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
476                                   " WRITE_DATA: (C:%d/H:%d/S:%d)\n", PCX, disk2_info->cyl, disk2_info->head, disk2_info->sector);
477                         if(disk2_info->head_sel != disk2_info->head) {
478                             printf("DISK2: " ADDRESS_FORMAT " WRITE_DATA: head_sel != head" NLP, PCX);
479                         }
480                         if(disk2_info->cyl != pDrive->track) { /* problem, should not happen, see above */
481                             sim_debug(ERROR_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
482                                       " WRITE_DATA = 0x%02x, cyl=%d, track=%d\n", PCX, cData, disk2_info->cyl, pDrive->track);
483                             pDrive->track = disk2_info->cyl; /* update track */
484                        }
485 
486                         sim_fseek((pDrive->uptr)->fileref, track_offset + (disk2_info->head_sel * pDrive->nsectors * (pDrive->sectsize + 3)), SEEK_SET);
487                         for(i=0;i<pDrive->nsectors;i++) {
488                             /* Read sector */
489                             file_offset = ftell((pDrive->uptr)->fileref);
490                             rtn = sim_fread(sdata.raw, 1, 3, (pDrive->uptr)->fileref);
491                             if (rtn != 3) {
492                                 sim_debug(ERROR_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
493                                           " WRITE_DATA: sim_fread error.\n", PCX);
494                             }
495                             if(sdata.u.header[2] == disk2_info->sector) {
496                                 if(sdata.u.header[0] != disk2_info->cyl) {
497                                     printf("DISK2: " ADDRESS_FORMAT
498                                            " WRITE_DATA Incorrect header: track" NLP, PCX);
499                                     disk2_info->timeout = 1;
500                                 }
501                                 if(sdata.u.header[1] != disk2_info->head) {
502                                     printf("DISK2: " ADDRESS_FORMAT
503                                            " WRITE_DATA Incorrect header: head" NLP, PCX);
504                                     disk2_info->timeout = 1;
505                                 }
506 
507                                 selchan_dma(sdata.u.data, pDrive->sectsize);
508                                 sim_fseek((pDrive->uptr)->fileref, file_offset+3, SEEK_SET);
509                                 sim_fwrite(sdata.u.data, 1, (pDrive->sectsize), (pDrive->uptr)->fileref);
510                                 break;
511                             }
512                             rtn = sim_fread(sdata.raw, 1, pDrive->sectsize, (pDrive->uptr)->fileref);
513                             if (rtn != (size_t)(pDrive->sectsize)) {
514                                 sim_debug(ERROR_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
515                                           " WRITE_DATA: sim_fread error.\n", PCX);
516                             }
517                             if(i == pDrive->nsectors) {
518                                 printf("DISK2: " ADDRESS_FORMAT " Sector not found" NLP, PCX);
519                                 disk2_info->timeout = 1;
520                             }
521                         }
522                         break;
523                     case DISK2_CMD_WRITE_HEADER:
524                         track_offset = pDrive->track * pDrive->nheads * pDrive->nsectors * (pDrive->sectsize + 3);
525                         sim_debug(CMD_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
526                                   " WRITE_HEADER Command: track=%d (%d), Head=%d, Sector=%d\n",
527                                   PCX, pDrive->track, disk2_info->cyl,
528                                   disk2_info->head_sel, disk2_info->hdr_sector);
529 
530                         i = disk2_info->hdr_sector;
531                         selchan_dma(sdata.raw, 3);
532                         sim_fseek((pDrive->uptr)->fileref, track_offset + (disk2_info->head_sel * (pDrive->sectsize + 3) * pDrive->nsectors) + (i * (pDrive->sectsize + 3)), SEEK_SET);
533                         sim_fwrite(sdata.raw, 1, 3, (pDrive->uptr)->fileref);
534 
535                         disk2_info->hdr_sector++;
536                         if(disk2_info->hdr_sector >= pDrive->nsectors) {
537                             disk2_info->hdr_sector = 0;
538                             disk2_info->timeout = 1;
539                         }
540                         break;
541                     case DISK2_CMD_READ_HEADER:
542                         track_offset = pDrive->track * pDrive->nheads * pDrive->nsectors * (pDrive->sectsize + 3);
543                         sim_debug(CMD_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
544                                   " READ_HEADER Command\n", PCX);
545                         sim_fseek((pDrive->uptr)->fileref, track_offset + (disk2_info->head_sel * pDrive->nsectors * (pDrive->sectsize + 3)), SEEK_SET);
546                         rtn = sim_fread(sdata.raw, 1, 3, (pDrive->uptr)->fileref);
547                         if (rtn != 3) {
548                             sim_debug(ERROR_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
549                                       " READ_HEADER: sim_fread error.\n", PCX);
550                         }
551                         selchan_dma(sdata.raw, 3);
552 
553                         break;
554                     default:
555                         printf("DISK2: " ADDRESS_FORMAT " Unknown CMD=%d" NLP, PCX, disk2_info->ctl_op);
556                         break;
557                 }
558 
559                 raise_disk2_interrupt();
560                 disk2_info->ctl_attn = 0;
561             }
562 
563             break;
564         case DISK2_DATA:
565             switch(disk2_info->ctl_op) {
566                 case DISK2_OP_DRIVE:
567                     switch(cData >> 4) {
568                         case 0x01:
569                             disk2_info->sel_drive = 0;
570                             break;
571                         case 0x02:
572                             disk2_info->sel_drive = 1;
573                             break;
574                         case 0x04:
575                             disk2_info->sel_drive = 2;
576                             break;
577                         case 0x08:
578                             disk2_info->sel_drive = 3;
579                             break;
580                         default:
581                             printf("DISK2: " ADDRESS_FORMAT
582                                    " Error, invalid drive select=0x%x" NLP, PCX, cData >> 4);
583                             break;
584                     }
585 
586                     disk2_info->head_sel = cData & 0x0F;
587 
588                     sim_debug(VERBOSE_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
589                               " Write DATA [DRIVE]=%d, Head=%d\n",
590                               PCX, disk2_info->sel_drive, disk2_info->head);
591                     break;
592                 case DISK2_OP_CYL:
593                     disk2_info->cyl = cData;
594                     sim_debug(VERBOSE_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
595                               " Write DATA [CYL] = %02x\n", PCX, cData);
596                     break;
597                 case DISK2_OP_HEAD:
598                     disk2_info->head = cData;
599                     sim_debug(VERBOSE_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
600                               " Write DATA [HEAD] = %02x\n", PCX, cData);
601                     break;
602                 case DISK2_OP_SECTOR:
603                     disk2_info->sector = cData;
604                     sim_debug(VERBOSE_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
605                               " Write Register [SECTOR] = %02x\n", PCX, cData);
606                     break;
607                 default:
608                     sim_debug(VERBOSE_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
609                               " Write Register unknown op [%d] = %02x\n",
610                               PCX, disk2_info->ctl_op, cData);
611                     break;
612             }
613     }
614 
615     return (result);
616 }
617 
618 #define SS1_VI1_INT         1   /* DISK2/DISK3 interrupts tied to VI1 */
619 
raise_disk2_interrupt(void)620 static void raise_disk2_interrupt(void)
621 {
622     sim_debug(IRQ_MSG, &disk2_dev, "DISK2: " ADDRESS_FORMAT
623               " Interrupt\n", PCX);
624 
625     raise_ss1_interrupt(SS1_VI1_INT);
626 
627 }
628