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[Core/SCD] improved CD drive seek time emulation (fixes Panic!/Switch intro)
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@ -879,10 +879,24 @@ void cdd_update(void)
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error("LBA = %d (track n°%d)\n", cdd.lba, cdd.index);
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#endif
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/* reading disc */
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if (cdd.status == CD_PLAY)
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/* seeking disc */
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if (cdd.status == CD_SEEK)
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{
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/* drive access latency */
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/* drive latency */
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if (cdd.latency > 0)
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{
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cdd.latency--;
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return;
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}
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/* drive is ready */
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cdd.status = CD_READY;
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}
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/* reading disc */
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else if (cdd.status == CD_PLAY)
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{
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/* drive latency */
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if (cdd.latency > 0)
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{
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cdd.latency--;
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@ -1216,7 +1230,17 @@ void cdd_process(void)
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(scd.regs[0x46>>1].byte.h * 10 + scd.regs[0x46>>1].byte.l)) * 75 +
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(scd.regs[0x48>>1].byte.h * 10 + scd.regs[0x48>>1].byte.l) - 150;
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/* update current LBA (TODO: add some delay ?) */
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/* CD drive seek time (required by Switch / Panic intro - see CD_PLAY command for details)*/
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if (lba < cdd.lba)
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{
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cdd.latency = (((cdd.lba - lba) * 120) / 270000);
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}
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else
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{
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cdd.latency = (((lba - cdd.lba) * 120) / 270000);
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}
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/* update current LBA */
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cdd.lba = lba;
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/* update current track index */
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@ -1241,7 +1265,7 @@ void cdd_process(void)
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scd.regs[0x36>>1].byte.h = 0x01;
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/* update status */
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cdd.status = CD_READY;
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cdd.status = CD_SEEK;
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scd.regs[0x38>>1].w = CD_SEEK << 8;
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scd.regs[0x3a>>1].w = 0x0000;
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scd.regs[0x3c>>1].w = 0x0000;
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