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SN76489: Correctly ignore bit 6 of the second data byte on the non-PSSJ types, fixes #4664.

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OBattler
2024-07-29 06:37:40 +02:00
parent cb275dd6a3
commit 9135083877
1 changed files with 15 additions and 6 deletions
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21
src/sound/snd_sn76489.c
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@@ -88,7 +88,7 @@ sn76489_write(UNUSED(uint16_t addr), uint8_t data, void *priv)
case 0:
sn76489->freqlo[3] = data & 0xf;
sn76489->latch[3] = (sn76489->freqlo[3] | (sn76489->freqhi[3] << 4)) << 6;
if (sn76489->extra_divide)
if (!sn76489->extra_divide)
sn76489->latch[3] &= 0x3ff;
if (!sn76489->latch[3])
sn76489->latch[3] = (sn76489->extra_divide ? 2048 : 1024) << 6;
@@ -101,7 +101,7 @@ sn76489_write(UNUSED(uint16_t addr), uint8_t data, void *priv)
case 0x20:
sn76489->freqlo[2] = data & 0xf;
sn76489->latch[2] = (sn76489->freqlo[2] | (sn76489->freqhi[2] << 4)) << 6;
if (sn76489->extra_divide)
if (!sn76489->extra_divide)
sn76489->latch[2] &= 0x3ff;
if (!sn76489->latch[2])
sn76489->latch[2] = (sn76489->extra_divide ? 2048 : 1024) << 6;
@@ -114,7 +114,7 @@ sn76489_write(UNUSED(uint16_t addr), uint8_t data, void *priv)
case 0x40:
sn76489->freqlo[1] = data & 0xf;
sn76489->latch[1] = (sn76489->freqlo[1] | (sn76489->freqhi[1] << 4)) << 6;
if (sn76489->extra_divide)
if (!sn76489->extra_divide)
sn76489->latch[1] &= 0x3ff;
if (!sn76489->latch[1])
sn76489->latch[1] = (sn76489->extra_divide ? 2048 : 1024) << 6;
@@ -132,7 +132,7 @@ sn76489_write(UNUSED(uint16_t addr), uint8_t data, void *priv)
sn76489->latch[0] = sn76489->latch[1];
else
sn76489->latch[0] = 0x400 << (data & 3);
if (sn76489->extra_divide)
if (!sn76489->extra_divide)
sn76489->latch[0] &= 0x3ff;
if (!sn76489->latch[0])
sn76489->latch[0] = (sn76489->extra_divide ? 2048 : 1024) << 6;
@@ -157,9 +157,12 @@ sn76489_write(UNUSED(uint16_t addr), uint8_t data, void *priv)
if (!sn76489->latch[0])
sn76489->latch[0] = 1024 << 6;
} else if ((sn76489->firstdat & 0x70) != 0x60) {
sn76489->freqhi[sn76489->lasttone] = data & 0x7F;
freq = sn76489->freqlo[sn76489->lasttone] | (sn76489->freqhi[sn76489->lasttone] << 4);
if (sn76489->extra_divide)
sn76489->freqhi[sn76489->lasttone] = data & 0x7F;
else
sn76489->freqhi[sn76489->lasttone] = data & 0x3F;
freq = sn76489->freqlo[sn76489->lasttone] | (sn76489->freqhi[sn76489->lasttone] << 4);
if (!sn76489->extra_divide)
freq &= 0x3ff;
if (!freq)
freq = sn76489->extra_divide ? 2048 : 1024;
@@ -174,6 +177,12 @@ void
sn74689_set_extra_divide(sn76489_t *sn76489, int enable)
{
sn76489->extra_divide = enable;
if (!enable) {
for (uint8_t c = 1; c < 4; c++)
sn76489->latch[c] &= ~(0x400 << 6);
sn76489->latch[0] &= ~(0x400 << 6);
}
}
void