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Framework fixes:

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- Initial memory allocation was using MEMF_LARGEST and did some unnecessary error checking and alignment.
- Trackloader skipped over the MFM gap between the end of the track and the start as optimization.
  However, it turns out that the gap can be smaller when written with non-Amiga controllers or faster
  rotation speeds. Reduced the skip from 300 words to 200 words, so it will work in these cases.
- There was a stupid bug in the trackloader that made the buffer-end detection non-functional.
This commit is contained in:
Chris Hodges 2024-10-09 00:38:45 +02:00
parent dd41bf2b6b
commit b1bd046594
2 changed files with 15 additions and 11 deletions
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19
source/framework/framework_trackloader.asm
View File

@ -819,13 +819,13 @@ fw_DecodeMfmTrack:
clr.l fw_TrackChecksum(a6)
.decode
.findsyncword
lea MFMBUFSIZE(a1),a2
lea MFMBUFSIZE(a1),a3
.syncloop
PUTMSG 70,<"LW %lx">,(a1)
cmp.w #MFMsync,(a1)+ ; search for a sync word
bne.s .syncloop
PUTMSG 60,<"Sync %lx at %p">,(a1),a1
cmp.l a1,a2 ; check for end of buffer
cmp.l a1,a3 ; check for end of buffer
beq .diskerror ; no more sync found
cmp.b (a1),d3 ; search for 0-nibble
bne.s .syncloop
@ -869,11 +869,20 @@ fw_DecodeMfmTrack:
cmp.b #1,d4
bne.s .nogapskip
PUTMSG 60,<"Skipping much of gap after decoding">
lea 300*2(a2),a2 ; gap of 300 words should be safe (340 is about normal)
; a gap of 300 words should be safe (340 is about normal),
; HOWEVER some drives (Greaseweazle?) may write with 2µs pulse length
; instead of the Amiga's 1.97356µs or faster rotational speeds,
; so the gap may become smaller!
; This broke some configurations apparently. Sorry.
lea 200*2(a2),a2 ; skip 200 words
.nogapskip
lea 6(a2),a1
cmp.w #(1<<11)-1,d7
bne .findsyncword ; decode until the bitmap is complete
beq .allsecsfound ; decode until the bitmap is complete
lea 6(a2),a1
cmp.l a1,a3 ; check for past end of buffer
bhi .findsyncword ; continue seeking sync word
bra .diskerror ; ooops, we're past the end of the buffer
.allsecsfound
PUTMSG 50,<"Track Checksum %lx">,fw_TrackChecksum(a6)
tst.l fw_TrackChecksum(a6) ; track total chksum OK?
bne .diskerror ; no, then retry

7
source/framework/trackmo_startupcode.asm
View File

@ -40,7 +40,7 @@ trackmo_AppInit:
CALL AvailMem
move.l d0,d2
beq.s .nofast
move.l #(MEMF_LARGEST|MEMF_FAST|MEMF_CLEAR),d1
move.l #MEMF_FAST|MEMF_CLEAR,d1
CALL AllocMem
move.l d0,fw_FastMemStack(a4)
bne.s .goodmem
@ -51,20 +51,15 @@ trackmo_AppInit:
move.l #(MEMF_LARGEST|MEMF_CHIP),d1
CALL AvailMem
move.l d0,d2
beq.s .memerr
move.l #(MEMF_CHIP|MEMF_CLEAR),d1
CALL AllocMem
addq.l #7,d0
and.w #-8,d0
move.l d0,fw_ChipMemStack(a4)
and.w #-8,d2
add.l d2,d0
move.l d0,fw_ChipMemStackEnd(a4)
move.l #(MEMF_LARGEST|MEMF_ANY),d1
CALL AvailMem
move.l d0,d2
beq.s .memerr
move.l #MEMF_CLEAR,d1
CALL AllocMem
move.l d0,fw_FastMemStack(a4)