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Inactive channels are not equivalent to channels with 0 volume.

This commit is contained in:
Lior Halphon 2018-02-11 22:50:15 +02:00
parent afcc66fb3c
commit bfb37884e1
1 changed files with 26 additions and 16 deletions
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42
Core/apu.c
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@ -26,11 +26,11 @@ static void update_sample(GB_gameboy_t *gb, unsigned index, uint8_t value, unsig
gb->apu.samples[index] = value;
if (gb->apu_output.sample_rate) {
unsigned left_volume = 0;
if (gb->io_registers[GB_IO_NR51] & (1 << index)) {
if (gb->apu.is_active[index] && (gb->io_registers[GB_IO_NR51] & (1 << index))) {
left_volume = (gb->io_registers[GB_IO_NR50] & 7) + 1;
}
unsigned right_volume = 0;
if (gb->io_registers[GB_IO_NR51] & (0x10 << index)) {
if (gb->apu.is_active[index] && (gb->io_registers[GB_IO_NR51] & (0x10 << index))) {
right_volume = ((gb->io_registers[GB_IO_NR50] >> 4) & 7) + 1;
}
GB_sample_t output = {(0xf - value) * left_volume, (0xf - value) * right_volume};
@ -82,11 +82,13 @@ static void render(GB_gameboy_t *gb)
unsigned left_volume = 0;
unsigned right_volume = 0;
for (unsigned i = GB_N_CHANNELS; i--;) {
if (mask & 1) {
left_volume += (gb->io_registers[GB_IO_NR50] & 7) * CH_STEP * 0xF;
}
if (mask & 0x10) {
right_volume += ((gb->io_registers[GB_IO_NR50] >> 4) & 7) * CH_STEP * 0xF;
if (gb->apu.is_active[i]) {
if (mask & 1) {
left_volume += (gb->io_registers[GB_IO_NR50] & 7) * CH_STEP * 0xF;
}
if (mask & 0x10) {
right_volume += ((gb->io_registers[GB_IO_NR50] >> 4) & 7) * CH_STEP * 0xF;
}
}
mask >>= 1;
}
@ -540,8 +542,8 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
if ((value & 0xF8) == 0) {
/* According to Blargg's test ROM this should disable the channel instantly
TODO: verify how "instant" the change is using PCM12 */
update_sample(gb, index, 0, 0);
gb->apu.is_active[index] = false;
update_sample(gb, index, 0, 0);
}
else if (gb->apu.is_active[index]) {
nrx2_glitch(&gb->apu.square_channels[index].current_volume, value, gb->io_registers[reg]);
@ -590,8 +592,9 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
gb->apu.square_channels[index].volume_countdown = gb->io_registers[index == GB_SQUARE_1 ? GB_IO_NR12 : GB_IO_NR22] & 7;
if ((gb->io_registers[index == GB_SQUARE_1 ? GB_IO_NR12 : GB_IO_NR22] & 0xF8) != 0) {
if ((gb->io_registers[index == GB_SQUARE_1 ? GB_IO_NR12 : GB_IO_NR22] & 0xF8) != 0 && !gb->apu.is_active[index]) {
gb->apu.is_active[index] = true;
update_square_sample(gb, index);
}
if (gb->apu.square_channels[index].pulse_length == 0) {
gb->apu.square_channels[index].pulse_length = 0x40;
@ -625,8 +628,8 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
gb->apu.square_channels[index].pulse_length = 0x3F;
}
else {
update_sample(gb, index, 0, 0);
gb->apu.is_active[index] = false;
update_sample(gb, index, 0, 0);
}
}
}
@ -682,7 +685,10 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
8);
}
}
gb->apu.is_active[GB_WAVE] = true;
if (!gb->apu.is_active[GB_WAVE]) {
gb->apu.is_active[GB_WAVE] = true;
update_sample(gb, GB_WAVE, 0, 0);
}
gb->apu.wave_channel.sample_countdown = (gb->apu.wave_channel.sample_length ^ 0x7FF) + 3;
gb->apu.wave_channel.current_sample_index = 0;
if (gb->apu.wave_channel.pulse_length == 0) {
@ -703,13 +709,16 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
gb->apu.wave_channel.pulse_length = 0xFF;
}
else {
update_sample(gb, GB_WAVE, 0, 0);
gb->apu.is_active[GB_WAVE] = false;
update_sample(gb, GB_WAVE, 0, 0);
}
}
}
gb->apu.wave_channel.length_enabled = value & 0x40;
gb->apu.is_active[GB_WAVE] &= gb->apu.wave_channel.enable;
if (gb->apu.is_active[GB_WAVE] && !gb->apu.wave_channel.enable) {
gb->apu.is_active[GB_WAVE] = false;
update_sample(gb, GB_WAVE, 0, 0);
}
break;
@ -725,8 +734,8 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
if ((value & 0xF8) == 0) {
/* According to Blargg's test ROM this should disable the channel instantly
TODO: verify how "instant" the change is using PCM12 */
update_sample(gb, GB_NOISE, 0, 0);
gb->apu.is_active[GB_NOISE] = false;
update_sample(gb, GB_NOISE, 0, 0);
}
else if (gb->apu.is_active[GB_NOISE]){
nrx2_glitch(&gb->apu.noise_channel.current_volume, value, gb->io_registers[reg]);
@ -783,8 +792,9 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
gb->apu.noise_channel.lfsr = 0;
gb->apu.noise_channel.volume_countdown = gb->io_registers[GB_IO_NR42] & 7;
if ((gb->io_registers[GB_IO_NR42] & 0xF8) != 0) {
if (!gb->apu.is_active[GB_NOISE] && (gb->io_registers[GB_IO_NR42] & 0xF8) != 0) {
gb->apu.is_active[GB_NOISE] = true;
update_sample(gb, GB_NOISE, 0, 0);
}
if (gb->apu.noise_channel.pulse_length == 0) {
@ -804,8 +814,8 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
gb->apu.noise_channel.pulse_length = 0x3F;
}
else {
update_sample(gb, GB_NOISE, 0, 0);
gb->apu.is_active[GB_NOISE] = false;
update_sample(gb, GB_NOISE, 0, 0);
}
}
}