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[Core/CD] improved CDD status report accuracy (fixes track looping with Mode 1 patched games using MSU-MD driver)

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ekeeke 2020-09-04 02:38:54 +02:00
parent fbb3448cea
commit be0edd898c
1 changed files with 32 additions and 3 deletions
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35
core/cd_hw/cdd.c
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@ -1795,7 +1795,7 @@ void cdd_process(void)
{
case 0x00: /* Get Drive Status */
{
/* RS0-RS8 are normally unchanged unless reported drive status needs to be updated (i.e previous drive command has been processed) */
/* RS0-RS1 are normally unchanged unless reported drive status needs to be updated (i.e previous drive command has been processed) */
/* Note: this function is called one 75hz frame ahead of CDD update so latency counter is always one step ahead of upcoming status */
/* Radical Rex and Annet Futatabi both need at least respectively 2 and 3 interrupts with 'playing' status returned before sectors start getting incremented */
if (cdd.latency <= 3)
@ -1806,8 +1806,37 @@ void cdd_process(void)
/* check if RS1 indicated invalid track infos (during seeking) */
if (scd.regs[0x38>>1].byte.l == 0x0f)
{
/* seeking has ended so we return valid track infos, e.g current track number in RS2-RS3 (fixes Lunar - The Silver Star) */
scd.regs[0x38>>1].byte.l = 0x02;
/* seeking has ended so we return valid track infos, e.g current absolute time by default (fixes Lunar - The Silver Star) */
int lba = cdd.lba + 150;
scd.regs[0x38>>1].byte.l = 0x00;
scd.regs[0x3a>>1].w = lut_BCD_16[(lba/75)/60];
scd.regs[0x3c>>1].w = lut_BCD_16[(lba/75)%60];
scd.regs[0x3e>>1].w = lut_BCD_16[(lba%75)];
scd.regs[0x40>>1].byte.h = cdd.toc.tracks[cdd.index].type ? 0x04 : 0x00; /* Current block flags in RS8 (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
}
/* otherwise, check if RS2-RS8 need to be updated */
else if (scd.regs[0x38>>1].byte.l == 0x00)
{
/* current absolute time */
int lba = cdd.lba + 150;
scd.regs[0x3a>>1].w = lut_BCD_16[(lba/75)/60];
scd.regs[0x3c>>1].w = lut_BCD_16[(lba/75)%60];
scd.regs[0x3e>>1].w = lut_BCD_16[(lba%75)];
scd.regs[0x40>>1].byte.h = cdd.toc.tracks[cdd.index].type ? 0x04 : 0x00; /* Current block flags in RS8 (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
}
else if (scd.regs[0x38>>1].byte.l == 0x01)
{
/* current track relative time */
int lba = abs(cdd.lba - cdd.toc.tracks[cdd.index].start);
scd.regs[0x3a>>1].w = lut_BCD_16[(lba/75)/60];
scd.regs[0x3c>>1].w = lut_BCD_16[(lba/75)%60];
scd.regs[0x3e>>1].w = lut_BCD_16[(lba%75)];
scd.regs[0x40>>1].byte.h = cdd.toc.tracks[cdd.index].type ? 0x04 : 0x00; /* Current block flags in RS8 (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
}
else if (scd.regs[0x38>>1].byte.l == 0x02)
{
/* current track number */
scd.regs[0x3a>>1].w = (cdd.index < cdd.toc.last) ? lut_BCD_16[cdd.index + 1] : 0x0A0A;
}
}