mame/src/lib/formats/thom_dsk.c
2014-03-31 10:23:22 +00:00

391 lines
10 KiB
C

/*********************************************************************
formats/thom_dsk.c
Thomson disk images
Based on work of Antoine Mine'
*********************************************************************/
#include <string.h>
#include "thom_dsk.h"
#include "basicdsk.h"
static const int sap_magic_num = 0xB3; /* simple XOR crypt */
static const char sap_header[] =
"\001SYSTEME D'ARCHIVAGE PUKALL S.A.P. "
"(c) Alexandre PUKALL Avril 1998";
static const UINT16 sap_crc[] =
{
0x0000, 0x1081, 0x2102, 0x3183, 0x4204, 0x5285, 0x6306, 0x7387,
0x8408, 0x9489, 0xa50a, 0xb58b, 0xc60c, 0xd68d, 0xe70e, 0xf78f,
};
struct sap_dsk_tag
{
int tracks;
int sector_size;
int sector_pos[80][16]; /* remember sector position in file */
};
static UINT16 thom_sap_crc( UINT8* data, int size )
{
int i;
UINT16 crc = 0xffff, crc2;
for ( i = 0; i < size; i++ )
{
crc2 = ( crc >> 4 ) ^ sap_crc[ ( crc ^ data[i] ) & 15 ];
crc = ( crc2 >> 4 ) ^ sap_crc[ ( crc2 ^ (data[i] >> 4) ) & 15 ];
}
return crc;
}
static struct sap_dsk_tag *get_tag(floppy_image_legacy *floppy)
{
struct sap_dsk_tag *tag;
tag = (sap_dsk_tag *)floppy_tag(floppy);
return tag;
}
static FLOPPY_IDENTIFY(sap_dsk_identify)
{
char header[0x100];
floppy_image_read(floppy, header, 0, sizeof(sap_header));
if (!memcmp( header, sap_header, sizeof(sap_header) ) )
{
*vote= 100;
} else {
*vote = 0;
}
return FLOPPY_ERROR_SUCCESS;
}
static int sap_get_heads_per_disk(floppy_image_legacy *floppy)
{
return 1;
}
static int sap_get_tracks_per_disk(floppy_image_legacy *floppy)
{
return get_tag(floppy)->tracks;
}
static floperr_t get_offset(floppy_image_legacy *floppy, int head, int track, int sector, int sector_is_index, UINT64 *offset)
{
UINT64 offs;
struct sap_dsk_tag *tag = get_tag(floppy);
/* translate the sector to a raw sector */
if (!sector_is_index)
{
sector -= 1;
}
/* check to see if we are out of range */
if ((head < 0) || (head >= 1) || (track < 0) || (track >=tag->tracks)
|| (sector < 0) || (sector >= 16))
return FLOPPY_ERROR_SEEKERROR;
offs = tag->sector_pos[track][sector];
if (offs <= 0 )
return FLOPPY_ERROR_SEEKERROR;
if (offset)
*offset = offs;
return FLOPPY_ERROR_SUCCESS;
}
static floperr_t internal_sap_read_sector(floppy_image_legacy *floppy, int head, int track, int sector, int sector_is_index, void *buffer, size_t buflen)
{
UINT64 offset;
floperr_t err;
int i;
UINT8 *buf;
err = get_offset(floppy, head, track, sector, sector_is_index, &offset);
if (err)
return err;
floppy_image_read(floppy, buffer, offset+4, buflen);
buf = (UINT8*)buffer;
for (i=0;i<buflen;i++) {
buf[i] ^= sap_magic_num;
}
return FLOPPY_ERROR_SUCCESS;
}
static floperr_t internal_sap_write_sector(floppy_image_legacy *floppy, int head, int track, int sector, int sector_is_index, const void *buffer, size_t buflen, int ddam)
{
UINT64 offset;
floperr_t err;
UINT8 buf[256+6];
UINT16 crc;
int i;
err = get_offset(floppy, head, track, sector, sector_is_index, &offset);
if (err)
return err;
/* buf = 4-byte header + sector + 2-byte CRC */
floppy_image_read(floppy, buf, offset, 4);
for (i=0;i<buflen;i++) {
buf[i+4] = ((UINT8*)buffer)[i];
}
crc = thom_sap_crc( buf, buflen+4 );
buf[buflen+4] = crc >> 8;
buf[buflen+5] = crc & 0xff;
for (i=0;i<buflen;i++) {
buf[i+4] ^= sap_magic_num;
}
floppy_image_write(floppy, buf, offset, buflen+6);
return FLOPPY_ERROR_SUCCESS;
}
static floperr_t sap_read_sector(floppy_image_legacy *floppy, int head, int track, int sector, void *buffer, size_t buflen)
{
return internal_sap_read_sector(floppy, head, track, sector, FALSE, buffer, buflen);
}
static floperr_t sap_write_sector(floppy_image_legacy *floppy, int head, int track, int sector, const void *buffer, size_t buflen, int ddam)
{
return internal_sap_write_sector(floppy, head, track, sector, FALSE, buffer, buflen, ddam);
}
static floperr_t sap_read_indexed_sector(floppy_image_legacy *floppy, int head, int track, int sector, void *buffer, size_t buflen)
{
return internal_sap_read_sector(floppy, head, track, sector, TRUE, buffer, buflen);
}
static floperr_t sap_write_indexed_sector(floppy_image_legacy *floppy, int head, int track, int sector, const void *buffer, size_t buflen, int ddam)
{
return internal_sap_write_sector(floppy, head, track, sector, TRUE, buffer, buflen, ddam);
}
static floperr_t sap_get_sector_length(floppy_image_legacy *floppy, int head, int track, int sector, UINT32 *sector_length)
{
floperr_t err;
err = get_offset(floppy, head, track, sector, FALSE, NULL);
if (err)
return err;
if (sector_length) {
*sector_length = get_tag(floppy)->sector_size;
}
return FLOPPY_ERROR_SUCCESS;
}
static floperr_t sap_get_indexed_sector_info(floppy_image_legacy *floppy, int head, int track, int sector_index, int *cylinder, int *side, int *sector, UINT32 *sector_length, unsigned long *flags)
{
floperr_t err;
UINT8 header[4];
UINT64 offset = 0;
sector_index += 1;
err = get_offset(floppy, head, track, sector_index, FALSE, &offset);
floppy_image_read(floppy, header, offset, 4);
if (cylinder)
*cylinder = header[2];
if (side)
*side = head;
if (sector)
*sector = header[3];
if (sector_length)
*sector_length = get_tag(floppy)->sector_size;
if (flags)
/* TODO: read DAM or DDAM and determine flags */
*flags = 0;
return err;
}
static floperr_t sap_post_format(floppy_image_legacy *floppy, option_resolution *params)
{
int track,sector;
int pos;
UINT8 buf[256], header[4];
struct sap_dsk_tag *tag;
tag = (struct sap_dsk_tag *) floppy_create_tag(floppy, sizeof(struct sap_dsk_tag));
/* default options */
if ( !tag->tracks )
{
tag->tracks = 80;
tag->sector_size = 256;
}
/* create SAP file header */
floppy_image_write( floppy, sap_header, 0, 66 );
for ( track = 0; track < 80; track++ )
for ( sector = 0; sector < 16; sector++ )
tag->sector_pos[track][sector] = 0;
/* create all sectors with valid header and CRC */
memset(buf, 0xe5, 256);
pos = 0x42;
header[0] = (tag->sector_size==128) ? 1 : 0;
header[1] = 0;
for ( track = 0, pos = 0x42; track < tag->tracks; track++ )
for ( sector = 0; sector < 16; sector++, pos += tag->sector_size + 6 ) {
tag->sector_pos[track][sector] = pos;
header[2] = track;
header[3] = sector + 1;
floppy_image_write(floppy, header, pos, 4);
sap_write_indexed_sector( floppy, 0, track, sector, buf, tag->sector_size, 0 );
}
return FLOPPY_ERROR_SUCCESS;
}
static FLOPPY_CONSTRUCT(sap_dsk_construct)
{
struct FloppyCallbacks *callbacks;
struct sap_dsk_tag *tag;
int j;
UINT8 fmt;
tag = (struct sap_dsk_tag *) floppy_create_tag(floppy, sizeof(struct sap_dsk_tag));
if (!tag)
return FLOPPY_ERROR_OUTOFMEMORY;
/* guess format */
floppy_image_read(floppy, &fmt, 0x42, 1);
if ( fmt==1 ) tag->sector_size = 128; else tag->sector_size = 256;
/* start with an empty offset table */
tag->tracks = 0;
for ( int i = 0; i < 80; i++ )
for ( j = 0; j < 16; j++ )
tag->sector_pos[i][j] = 0;
/* count tracks & fill sector offset table */
for ( UINT64 i = 0x42; i+4 < floppy_image_size(floppy); i += tag->sector_size + 6 ) // CRC 2 bytes + 4 bytes sector header
{
UINT8 sector, track;
floppy_image_read(floppy, &track, i+2, 1);
floppy_image_read(floppy, &sector, i+3, 1);
if ( track >= 80 || sector < 1 || sector > 16 ) continue;
if ( track > tag->tracks ) tag->tracks = track+1;
tag->sector_pos[track][sector-1] = i;
}
callbacks = floppy_callbacks(floppy);
callbacks->read_sector = sap_read_sector;
callbacks->write_sector = sap_write_sector;
callbacks->read_indexed_sector = sap_read_indexed_sector;
callbacks->write_indexed_sector = sap_write_indexed_sector;
callbacks->get_sector_length = sap_get_sector_length;
callbacks->get_heads_per_disk = sap_get_heads_per_disk;
callbacks->get_tracks_per_disk = sap_get_tracks_per_disk;
callbacks->get_indexed_sector_info = sap_get_indexed_sector_info;
callbacks->post_format = sap_post_format;
return FLOPPY_ERROR_SUCCESS;
}
static FLOPPY_IDENTIFY(qdd_dsk_identify)
{
*vote = (floppy_image_size(floppy) == (51200)) ? 100 : 0;
return FLOPPY_ERROR_SUCCESS;
}
/* fixed interlacing map for QDDs */
static int thom_qdd_map[400];
static int qdd_translate_sector(floppy_image_legacy *floppy, int sector)
{
return thom_qdd_map[sector-1];
}
static void thom_qdd_compute_map ( void )
{
/* this map is hardcoded in the QDD BIOS */
static const int p[6][4] =
{
{ 20, 2, 14, 8 }, { 21, 19, 13, 7 },
{ 22, 18, 12, 6 }, { 23, 17, 11, 5 },
{ 24, 16, 10, 4 }, { 1, 15, 9, 3 }
};
static const int q[4] = { 0, 8, 4, 12 };
int t, s;
for ( t = 0; t < 24; t++ )
{
for ( s = 0; s < 16; s++ )
{
thom_qdd_map[ t*16 + s ] = p[ t/4 ][ s%4 ] * 16 + (s/4) + 4*(t%4);
}
}
for ( s = 0; s < 16; s++ )
{
thom_qdd_map[ 24*16 + s ] = q[ s%4 ] + (s/4);
}
}
static FLOPPY_CONSTRUCT(qdd_dsk_construct)
{
struct basicdsk_geometry geometry;
thom_qdd_compute_map();
memset(&geometry, 0, sizeof(geometry));
geometry.heads = 1;
geometry.first_sector_id = 1;
geometry.sector_length = 128;
geometry.tracks = 1;
geometry.sectors = 400;
geometry.translate_sector = qdd_translate_sector;
return basicdsk_construct(floppy, &geometry);
}
/* ----------------------------------------------------------------------- */
LEGACY_FLOPPY_OPTIONS_START(thomson)
LEGACY_FLOPPY_OPTION(fdmfm2, "fd", "Thomson FD (MFM) 80 tracks disk image (3\"1/2 DD)", basicdsk_identify_default, basicdsk_construct_default, NULL,
HEADS([1])
TRACKS([80])
SECTORS([16])
SECTOR_LENGTH([256])
FIRST_SECTOR_ID([1]))
LEGACY_FLOPPY_OPTION(fdmfm, "fd", "Thomson FD (MFM) 40 tracks disk image (5\"1/4 DD)", basicdsk_identify_default, basicdsk_construct_default, NULL,
HEADS([1])
TRACKS([40])
SECTORS([16])
SECTOR_LENGTH([256])
FIRST_SECTOR_ID([1]))
LEGACY_FLOPPY_OPTION(fd2, "fd", "Thomson FD (FM) 80 tracks disk image (3\"1/2 SD)", basicdsk_identify_default, basicdsk_construct_default, NULL,
HEADS([1])
TRACKS([80])
SECTORS([16])
SECTOR_LENGTH([128])
FIRST_SECTOR_ID([1]))
LEGACY_FLOPPY_OPTION(fd, "fd", "Thomson FD (FM) 40 tracks disk image (5\"1/4 SD)", basicdsk_identify_default, basicdsk_construct_default, NULL,
HEADS([1])
TRACKS([40])
SECTORS([16])
SECTOR_LENGTH([128])
FIRST_SECTOR_ID([1]))
LEGACY_FLOPPY_OPTION(sap,"sap", "Thomson SAP floppy disk image", sap_dsk_identify, sap_dsk_construct, NULL, NULL)
LEGACY_FLOPPY_OPTION(qdd,"qd", "Thomson QDD floppy disk image (2\"8 SD)", qdd_dsk_identify, qdd_dsk_construct, NULL,
HEADS([1])
TRACKS([1])
SECTORS([400])
SECTOR_LENGTH([128])
FIRST_SECTOR_ID([0]))
LEGACY_FLOPPY_OPTIONS_END