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[Core/SCD] improved CDD emulation (fixes Final Fight CD intro when seek time is emulated)

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This commit is contained in:
EkeEke 2013-05-12 21:55:52 +02:00
parent c3db7ade7d
commit 6a6a13b4b2
2 changed files with 72 additions and 65 deletions
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129
source/cd_hw/cdd.c
View File

@ -876,7 +876,7 @@ void cdd_read_audio(unsigned int samples)
void cdd_update(void)
{
#ifdef LOG_CDD
error("LBA = %d (track n°%d)\n", cdd.lba, cdd.index);
error("LBA = %d (track n°%d)(latency=%d)\n", cdd.lba, cdd.index, cdd.latency);
#endif
/* seeking disc */
@ -1034,17 +1034,20 @@ void cdd_process(void)
{
case 0x00: /* Drive Status */
{
/* RS1-RS8 unchanged */
scd.regs[0x38>>1].byte.h = cdd.status;
break;
}
case 0x01: /* Stop Drive */
{
/* update status */
cdd.status = cdd.loaded ? CD_STOP : NO_DISC;
/* no audio track playing */
scd.regs[0x36>>1].byte.h = 0x01;
/* RS1-RS8 ignored, expects 0x0 ("no disc" ?) in RS0 once */
scd.regs[0x38>>1].w = 0x0000;
scd.regs[0x3a>>1].w = 0x0000;
scd.regs[0x3c>>1].w = 0x0000;
@ -1066,7 +1069,7 @@ void cdd_process(void)
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.index ? 0x00 : 0x04; /* Current block flags (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
scd.regs[0x40>>1].byte.h = cdd.index ? 0x00 : 0x04; /* Current block flags in RS8 (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
break;
}
@ -1077,7 +1080,7 @@ void cdd_process(void)
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.index ? 0x00 : 0x04; /* Current block flags (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
scd.regs[0x40>>1].byte.h = cdd.index ? 0x00 : 0x04; /* Current block flags in RS8 (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
break;
}
@ -1108,7 +1111,7 @@ void cdd_process(void)
scd.regs[0x3a>>1].w = 0x0001;
scd.regs[0x3c>>1].w = lut_BCD_16[cdd.toc.last];
scd.regs[0x3e>>1].w = 0x0000; /* Drive Version (?) in RS6-RS7 */
scd.regs[0x40>>1].byte.h = 0x00; /* Lead-In flags (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
scd.regs[0x40>>1].byte.h = 0x00; /* Lead-In flags in RS8 (bit0 = mute status, bit1: pre-emphasis status, bit2: track type) */
break;
}
@ -1150,37 +1153,38 @@ void cdd_process(void)
(scd.regs[0x46>>1].byte.h * 10 + scd.regs[0x46>>1].byte.l)) * 75 +
(scd.regs[0x48>>1].byte.h * 10 + scd.regs[0x48>>1].byte.l) - 150;
/* CD drive access time */
/* CD drive latency */
if (!cdd.latency)
{
/* Fixes a few games hanging during intro because they expect data to be read with some delay */
/* Radical Rex needs at least one interrupt delay */
/* Wolf Team games (Anet Futatabi, Cobra Command, Road Avenger & Time Gal) need at least 6 interrupts delay */
/* Space Adventure Cobra (2nd morgue scene) needs at least 13 interrupts delay (incl. seek time, so 6 here is OK) */
/* Space Adventure Cobra (2nd morgue scene) needs at least 13 interrupts delay (incl. seek time, so 6 is OK) */
/* Jeopardy & ESPN Sunday Night NFL are picky about this as well: 7 interrupts delay (+ seek time) seems OK */
cdd.latency = 7;
}
/* CD drive seek time */
/* Some delay is especially needed when playing audio tracks located at the end of the disc (ex: Sonic CD intro) */
/* max. seek time = 1.5s = 1.5 x 75 = 112.5 CDD interrupts (rounded to 120) for 270000 sectors max on disc */
/* Note: this is only a rough approximation, on real hardware, drive seek time is much likely not linear */
if (lba < cdd.lba)
{
cdd.latency += (((cdd.lba - lba) * 120) / 270000);
}
else
/* max. seek time = 1.5 s = 1.5 x 75 = 112.5 CDD interrupts (rounded to 120) for 270000 sectors max on disc. */
/* Note: This is only a rough approximation since, on real hardware, seek time is much likely not linear and */
/* latency much larger than above value, but this model works fine for Sonic CD (track 26 playback needs to */
/* be enough delayed to start in sync with intro sequence, as compared with real hardware recording). */
if (lba > cdd.lba)
{
cdd.latency += (((lba - cdd.lba) * 120) / 270000);
}
else
{
cdd.latency += (((cdd.lba - lba) * 120) / 270000);
}
/* update current LBA */
cdd.lba = lba;
/* update current track index */
while ((cdd.toc.tracks[index].end <= lba) && (index < cdd.toc.last)) index++;
cdd.index = index;
/* no audio track playing */
scd.regs[0x36>>1].byte.h = 0x01;
/* seek to current block */
if (!index)
{
@ -1207,11 +1211,13 @@ void cdd_process(void)
}
}
/* update current LBA */
cdd.lba = lba;
/* no audio track playing (yet) */
scd.regs[0x36>>1].byte.h = 0x01;
/* update status */
cdd.status = CD_PLAY;
/* return current track number in RS2-RS3 */
scd.regs[0x38>>1].w = (CD_PLAY << 8) | 0x02;
scd.regs[0x3a>>1].w = (cdd.index < cdd.toc.last) ? lut_BCD_16[index + 1] : 0x0A0A;
scd.regs[0x3c>>1].w = 0x0000;
@ -1230,14 +1236,16 @@ void cdd_process(void)
(scd.regs[0x46>>1].byte.h * 10 + scd.regs[0x46>>1].byte.l)) * 75 +
(scd.regs[0x48>>1].byte.h * 10 + scd.regs[0x48>>1].byte.l) - 150;
/* CD drive seek time (required by Switch / Panic intro - see CD_PLAY command for details)*/
if (lba < cdd.lba)
/* CD drive seek time */
/* We are using similar linear model as above, although still not exactly accurate, */
/* it works fine for Switch/Panic! intro (needs at least 30 interrupts while seeking) */
if (lba > cdd.lba)
{
cdd.latency = (((cdd.lba - lba) * 120) / 270000);
cdd.latency = ((lba - cdd.lba) * 120) / 270000;
}
else
{
cdd.latency = (((lba - cdd.lba) * 120) / 270000);
cdd.latency = ((cdd.lba - lba) * 120) / 270000;
}
/* update current LBA */
@ -1266,12 +1274,14 @@ void cdd_process(void)
/* update status */
cdd.status = CD_SEEK;
scd.regs[0x38>>1].w = CD_SEEK << 8;
/* unknown RS1-RS8 values (returning 0xF in RS1 invalidates track infos usually returned in RS2-RS8, which fixes Final Fight CD intro when seek time is emulated) */
scd.regs[0x38>>1].w = (CD_SEEK << 8) | 0x0f;
scd.regs[0x3a>>1].w = 0x0000;
scd.regs[0x3c>>1].w = 0x0000;
scd.regs[0x3e>>1].w = 0x0000;
scd.regs[0x40>>1].w = ~CD_SEEK & 0x0f;
return;
scd.regs[0x40>>1].w = ~(CD_SEEK + 0xf) & 0x0f;
break;
}
case 0x06: /* Pause */
@ -1279,65 +1289,58 @@ void cdd_process(void)
/* no audio track playing */
scd.regs[0x36>>1].byte.h = 0x01;
/* update status */
cdd.status = CD_READY;
scd.regs[0x38>>1].w = CD_READY << 8;
scd.regs[0x3a>>1].w = 0x0000;
scd.regs[0x3c>>1].w = 0x0000;
scd.regs[0x3e>>1].w = 0x0000;
scd.regs[0x40>>1].w = ~CD_READY & 0x0f;
return;
/* update status (RS1-RS8 unchanged) */
cdd.status = scd.regs[0x38>>1].byte.h = CD_READY;
break;
}
case 0x07: /* Resume */
{
/* update status */
cdd.status = CD_PLAY;
scd.regs[0x38>>1].w = (CD_PLAY << 8) | 0x02;
scd.regs[0x3a>>1].w = (cdd.index < cdd.toc.last) ? lut_BCD_16[cdd.index + 1] : 0x0A0A;
scd.regs[0x3c>>1].w = 0x0000;
scd.regs[0x3e>>1].w = 0x0000;
scd.regs[0x40>>1].byte.h = 0x00;
/* update status (RS1-RS8 unchanged) */
cdd.status = scd.regs[0x38>>1].byte.h = CD_PLAY;
break;
}
case 0x08: /* Forward Scan */
{
/* reset scanning direction / speed */
cdd.scanOffset = CD_SCAN_SPEED;
cdd.status = CD_SCAN;
scd.regs[0x38>>1].w = (CD_SCAN << 8) | 0x02;
scd.regs[0x3a>>1].w = (cdd.index < cdd.toc.last) ? lut_BCD_16[cdd.index + 1] : 0x0A0A;
scd.regs[0x3c>>1].w = 0x0000;
scd.regs[0x3e>>1].w = 0x0000;
scd.regs[0x40>>1].byte.h = 0x00;
/* update status (RS1-RS8 unchanged) */
cdd.status = scd.regs[0x38>>1].byte.h = CD_SCAN;
break;
}
case 0x09: /* Rewind Scan */
{
/* reset scanning direction / speed */
cdd.scanOffset = -CD_SCAN_SPEED;
cdd.status = CD_SCAN;
scd.regs[0x38>>1].w = (CD_SCAN << 8) | 0x02;
scd.regs[0x3a>>1].w = (cdd.index < cdd.toc.last) ? lut_BCD_16[cdd.index + 1] : 0x0A0A;
scd.regs[0x3c>>1].w = 0x0000;
scd.regs[0x3e>>1].w = 0x0000;
scd.regs[0x40>>1].byte.h = 0x00;
/* update status (RS1-RS8 unchanged) */
cdd.status = scd.regs[0x38>>1].byte.h = CD_SCAN;
break;
}
case 0x0a: /* ??? (usually sent before first & last CD_PLAY command) */
case 0x0a: /* N-Track Jump Control ? (usually sent before CD_SEEK or CD_PLAY commands) */
{
/* TC3 corresponds to seek direction (00=forward, FF=reverse) */
/* TC4-TC7 are related to seek length (4x4 bits i.e parameter values are between -65535 and +65535) */
/* Maybe related to number of auto-sequenced track jumps/moves for CD DSP (cf. CXD2500BQ datasheet) */
/* also see US Patent nr. 5222054 for a detailled description of seeking operation using Track Jump */
/* no audio track playing */
scd.regs[0x36>>1].byte.h = 0x01;
/* RS0-RS8 values taken from Gens */
/* update status */
cdd.status = CD_READY;
scd.regs[0x38>>1].w = CD_READY << 8;
/* unknown RS0-RS8 values (returning 0xF in RS1 invalidates track infos usually returned in RS2-RS8) */
scd.regs[0x38>>1].w = (CD_READY << 8) | 0x0f;
scd.regs[0x3a>>1].w = 0x0000;
scd.regs[0x3c>>1].w = 0x0001;
scd.regs[0x3e>>1].w = 0x0001;
scd.regs[0x40>>1].w = ~(CD_READY + 2) & 0x0f;
scd.regs[0x3c>>1].w = 0x0000;
scd.regs[0x3e>>1].w = 0x0000;
scd.regs[0x40>>1].w = ~(CD_READY + 0xf) & 0x0f;
return;
}
@ -1346,7 +1349,10 @@ void cdd_process(void)
/* no audio track playing */
scd.regs[0x36>>1].byte.h = 0x01;
/* update status */
cdd.status = cdd.loaded ? CD_STOP : NO_DISC;
/* RS1-RS8 ignored, expects 0x0 ("no disc" ?) in RS0 once */
scd.regs[0x38>>1].w = 0x0000;
scd.regs[0x3a>>1].w = 0x0000;
scd.regs[0x3c>>1].w = 0x0000;
@ -1364,12 +1370,13 @@ void cdd_process(void)
/* no audio track playing */
scd.regs[0x36>>1].byte.h = 0x01;
/* update status (RS1-RS8 ignored) */
cdd.status = CD_OPEN;
scd.regs[0x38>>1].w = 0x0e00;
scd.regs[0x38>>1].w = CD_OPEN << 8;
scd.regs[0x3a>>1].w = 0x0000;
scd.regs[0x3c>>1].w = 0x0000;
scd.regs[0x3e>>1].w = 0x0000;
scd.regs[0x40>>1].w = 0x0001;
scd.regs[0x40>>1].w = ~CD_OPEN & 0x0f;
#ifdef CD_TRAY_CALLBACK
CD_TRAY_CALLBACK

2
source/cd_hw/cdd.h
View File

@ -48,7 +48,7 @@
#define CD_SEEK 0x02
#define CD_SCAN 0x03
#define CD_READY 0x04
#define CD_OPEN 0x05
#define CD_OPEN 0x05 /* similar to 0x0E ? */
#define CD_STOP 0x09
#define CD_END 0x0C