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Even more VSU edge cases

This commit is contained in:
Guy Perfect 2025-03-01 15:42:16 -06:00
parent 459a16076a
commit dd1045553b
2 changed files with 24 additions and 15 deletions
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9
core/vb.c
View File

@ -360,10 +360,11 @@ struct VB {
uint8_t shift; /* Sweep shift amount */
/* Other state */
uint32_t clocks; /* Clocks until modification */
uint8_t modmask; /* Modifications masked */
uint16_t next; /* Next frequency value */
int sample; /* Current sample index */
uint32_t clocks; /* Clocks until modification */
uint8_t modmask; /* Modifications masked */
uint8_t freqmask; /* Frequency mask */
uint16_t next; /* Next frequency value */
int sample; /* Current sample index */
} freqmod;
/* Channel 6 noise generator */

30
core/vsu.c
View File

@ -83,11 +83,11 @@ static void vsuNextFreqMod(VB *sim, Channel *chan) {
/* Modulation */
else {
next = (int32_t) chan->freq.written +
sim->vsu.modulation[sim->vsu.freqmod.sample];
if (next < 0)
next = 0;
if (next > 2047)
next = 2047;
sim->vsu.modulation[sim->vsu.freqmod.sample] & 0x7FF;
if (sim->vsu.freqmod.freqmask == 1)
next = (next & 0x700) | (chan->freq.written & 0x0FF);
else if (sim->vsu.freqmod.freqmask == 2) {
next = (next & 0x0FF) | (chan->freq.written & 0x700);
}
/* Configure state */
@ -257,8 +257,10 @@ static void vsuWriteFQH(VB *sim, int index, uint16_t value) {
value = value << 8 & 0x0700;
chan->freq.current = (chan->freq.current & 0x00FF) | value;
chan->freq.written = (chan->freq.written & 0x00FF) | value;
if (index == 4)
vsuNextFreqMod(sim, chan);
if (index != 4)
return;
sim->vsu.freqmod.freqmask = 2;
vsuNextFreqMod(sim, chan);
}
/* Write a value to S*FQL */
@ -266,8 +268,10 @@ static void vsuWriteFQL(VB *sim, int index, uint8_t value) {
Channel *chan = &sim->vsu.channels[index];
chan->freq.current = (chan->freq.current & 0x0700) | value;
chan->freq.written = (chan->freq.written & 0x0700) | value;
if (index == 4)
vsuNextFreqMod(sim, chan);
if (index != 4)
return;
sim->vsu.freqmod.freqmask = 1;
vsuNextFreqMod(sim, chan);
}
/* Write a value to S*INT */
@ -510,6 +514,7 @@ static void vsuReset(VB *sim) {
sim->vsu.freqmod.func = 0;
sim->vsu.freqmod.interval = 0;
sim->vsu.freqmod.modmask = 0;
sim->vsu.freqmod.freqmask = 0;
sim->vsu.freqmod.next = 0;
sim->vsu.freqmod.rep = 0;
sim->vsu.freqmod.sample = 0;
@ -536,11 +541,14 @@ static void vsuWrite(VB*sim,uint32_t address,int type,int32_t value,int debug){
}
/* Unmapped */
if (address & 3)
if (address & 1)
return;
/* Working variables */
address &= 0x7FF;
address &= 0x7FC;
/* Clear frequency mask */
sim->vsu.freqmod.freqmask = 0;
/* Wave memory */
if (address < 0x280) {