mirror of https://github.com/bsnes-emu/bsnes.git
131 lines
3.2 KiB
C++
131 lines
3.2 KiB
C++
auto DSP::calculateFIR(bool channel, int index) -> int {
|
|
int sample = state.echoHistory[channel][(uint3)(state.echoHistoryOffset + index + 1)];
|
|
return (sample * (int8)REG(FIR + index * 0x10)) >> 6;
|
|
}
|
|
|
|
auto DSP::echoOutput(bool channel) -> int {
|
|
int output = (int16)((state._mainOut[channel] * (int8)REG(MVOLL + channel * 0x10)) >> 7)
|
|
+ (int16)((state._echoIn [channel] * (int8)REG(EVOLL + channel * 0x10)) >> 7);
|
|
return sclamp<16>(output);
|
|
}
|
|
|
|
auto DSP::echoRead(bool channel) -> void {
|
|
uint addr = state._echoPointer + channel * 2;
|
|
uint8 lo = smp.apuram[(uint16)(addr + 0)];
|
|
uint8 hi = smp.apuram[(uint16)(addr + 1)];
|
|
int s = (int16)((hi << 8) + lo);
|
|
state.echoHistory[channel][state.echoHistoryOffset] = s >> 1;
|
|
}
|
|
|
|
auto DSP::echoWrite(bool channel) -> void {
|
|
if(!(state._echoDisabled & 0x20)) {
|
|
uint addr = state._echoPointer + channel * 2;
|
|
int s = state._echoOut[channel];
|
|
smp.apuram[(uint16)(addr + 0)] = s;
|
|
smp.apuram[(uint16)(addr + 1)] = s >> 8;
|
|
}
|
|
|
|
state._echoOut[channel] = 0;
|
|
}
|
|
|
|
auto DSP::echo22() -> void {
|
|
//history
|
|
state.echoHistoryOffset++;
|
|
|
|
state._echoPointer = (uint16)((state._esa << 8) + state.echoOffset);
|
|
echoRead(0);
|
|
|
|
//FIR
|
|
int l = calculateFIR(0, 0);
|
|
int r = calculateFIR(1, 0);
|
|
|
|
state._echoIn[0] = l;
|
|
state._echoIn[1] = r;
|
|
}
|
|
|
|
auto DSP::echo23() -> void {
|
|
int l = calculateFIR(0, 1) + calculateFIR(0, 2);
|
|
int r = calculateFIR(1, 1) + calculateFIR(1, 2);
|
|
|
|
state._echoIn[0] += l;
|
|
state._echoIn[1] += r;
|
|
|
|
echoRead(1);
|
|
}
|
|
|
|
auto DSP::echo24() -> void {
|
|
int l = calculateFIR(0, 3) + calculateFIR(0, 4) + calculateFIR(0, 5);
|
|
int r = calculateFIR(1, 3) + calculateFIR(1, 4) + calculateFIR(1, 5);
|
|
|
|
state._echoIn[0] += l;
|
|
state._echoIn[1] += r;
|
|
}
|
|
|
|
auto DSP::echo25() -> void {
|
|
int l = state._echoIn[0] + calculateFIR(0, 6);
|
|
int r = state._echoIn[1] + calculateFIR(1, 6);
|
|
|
|
l = (int16)l;
|
|
r = (int16)r;
|
|
|
|
l += (int16)calculateFIR(0, 7);
|
|
r += (int16)calculateFIR(1, 7);
|
|
|
|
state._echoIn[0] = sclamp<16>(l) & ~1;
|
|
state._echoIn[1] = sclamp<16>(r) & ~1;
|
|
}
|
|
|
|
auto DSP::echo26() -> void {
|
|
//left output volumes
|
|
//(save sample for next clock so we can output both together)
|
|
state._mainOut[0] = echoOutput(0);
|
|
|
|
//echo feedback
|
|
int l = state._echoOut[0] + (int16)((state._echoIn[0] * (int8)REG(EFB)) >> 7);
|
|
int r = state._echoOut[1] + (int16)((state._echoIn[1] * (int8)REG(EFB)) >> 7);
|
|
|
|
state._echoOut[0] = sclamp<16>(l) & ~1;
|
|
state._echoOut[1] = sclamp<16>(r) & ~1;
|
|
}
|
|
|
|
auto DSP::echo27() -> void {
|
|
//output
|
|
int outl = state._mainOut[0];
|
|
int outr = echoOutput(1);
|
|
state._mainOut[0] = 0;
|
|
state._mainOut[1] = 0;
|
|
|
|
//todo: global muting isn't this simple
|
|
//(turns DAC on and off or something, causing small ~37-sample pulse when first muted)
|
|
if(REG(FLG) & 0x40) {
|
|
outl = 0;
|
|
outr = 0;
|
|
}
|
|
|
|
//output sample to DAC
|
|
stream->sample(outl / 32768.0, outr / 32768.0);
|
|
}
|
|
|
|
auto DSP::echo28() -> void {
|
|
state._echoDisabled = REG(FLG);
|
|
}
|
|
|
|
auto DSP::echo29() -> void {
|
|
state._esa = REG(ESA);
|
|
|
|
if(!state.echoOffset) state.echoLength = (REG(EDL) & 0x0f) << 11;
|
|
|
|
state.echoOffset += 4;
|
|
if(state.echoOffset >= state.echoLength) state.echoOffset = 0;
|
|
|
|
//write left echo
|
|
echoWrite(0);
|
|
|
|
state._echoDisabled = REG(FLG);
|
|
}
|
|
|
|
auto DSP::echo30() -> void {
|
|
//write right echo
|
|
echoWrite(1);
|
|
}
|