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Pass in sector table for logical-physical orders

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We were not encoding data properly, because in DOS 3.3 and ProDOS,
sectors must be interleaved on disk media (whereas in the original image
form, data is laid out in a linear fashion).

This solves a bug where we erroneously encountered a "bad" opcode (a7)
in the program code.
This commit is contained in:
Peter Evans 2018-02-19 18:49:37 -06:00
parent 3ab654c306
commit 508be6458a
3 changed files with 23 additions and 11 deletions
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4
include/apple2.enc.h
View File

@ -62,8 +62,8 @@
extern int apple2_enc_4n4(vm_segment *, int, vm_8bit);
extern int apple2_enc_sector(vm_segment *, vm_segment *, int, int);
extern int apple2_enc_sector_header(vm_segment *, int, int, int);
extern int apple2_enc_track(vm_segment *, vm_segment *, int, int);
extern vm_segment *apple2_enc_dos(vm_segment *);
extern int apple2_enc_track(vm_segment *, vm_segment *, const int *, int, int);
extern vm_segment *apple2_enc_dos(vm_segment *, const int *);
extern vm_segment *apple2_enc_nib(vm_segment *);
#endif

15
src/apple2.dd.c
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@ -14,6 +14,16 @@
#include "apple2.enc.h"
#include "apple2.h"
static int sector_dos33[] = {
0x0, 0x7, 0xe, 0x6, 0xd, 0x5, 0xc, 0x4,
0xb, 0x3, 0xa, 0x2, 0x9, 0x1, 0x8, 0xf,
};
static int sector_prodos[] = {
0x0, 0x8, 0x1, 0x9, 0x2, 0xa, 0x3, 0xb,
0x4, 0xc, 0x5, 0xd, 0x6, 0xe, 0x7, 0xf,
};
/*
* Create a new disk drive. We do not create a memory segment for the
* drive right away, as the size of said data can be variable based on
@ -113,8 +123,11 @@ apple2_dd_encode(apple2dd *drive)
break;
case DD_DOS33:
drive->data = apple2_enc_dos(drive->image, sector_dos33);
break;
case DD_PRODOS:
drive->data = apple2_enc_dos(drive->image);
drive->data = apple2_enc_dos(drive->image, sector_prodos);
break;
default:

15
src/apple2.enc.c
View File

@ -39,7 +39,7 @@ static vm_8bit gcr62[] = {
* 3.2 and 3.1 (which use 5-and-3 encoding).
*/
vm_segment *
apple2_enc_dos(vm_segment *src)
apple2_enc_dos(vm_segment *src, const int *sectab)
{
vm_segment *dest;
int i, doff = 0;
@ -58,7 +58,7 @@ apple2_enc_dos(vm_segment *src)
// away with just using tracks-and-sectors. In particular, DOS 3.3
// has 35 tracks of 4096 bytes each.
for (i = 0; i < 35; i++) {
doff += apple2_enc_track(dest, src, doff, i);
doff += apple2_enc_track(dest, src, sectab, doff, i);
}
return dest;
@ -105,12 +105,12 @@ apple2_enc_nib(vm_segment *src)
* written into dest.
*/
int
apple2_enc_track(vm_segment *dest, vm_segment *src,
apple2_enc_track(vm_segment *dest, vm_segment *src, const int *sectab,
int doff, int track)
{
int soff = track * ENC_DTRACK;
int toff = track * ENC_DTRACK;
int orig = doff;
int sect, i;
int sect, i, soff;
// We'll start off with some self-sync bytes to separate this track
// from any other
@ -119,13 +119,12 @@ apple2_enc_track(vm_segment *dest, vm_segment *src,
}
for (sect = 0; sect < 16; sect++) {
soff = toff + (ENC_DSECTOR * sectab[sect]);
// Each sector has a header with some metadata, plus some
// markers and padding.
doff += apple2_enc_sector_header(dest, doff, track, sect);
doff += apple2_enc_sector(dest, src, doff, soff);
// We're moving here in 256-byte blocks
soff += ENC_DSECTOR;
}
return doff - orig;