Files
yaze/src/app/emu/audio/apu.cc
2023-12-06 01:32:59 -05:00

139 lines
3.3 KiB
C++

#include "app/emu/audio/apu.h"
#include <cstdint>
#include <functional>
#include <iostream>
#include <vector>
#include "app/emu/audio/dsp.h"
#include "app/emu/audio/spc700.h"
#include "app/emu/cpu/clock.h"
#include "app/emu/memory/memory.h"
namespace yaze {
namespace app {
namespace emu {
void APU::Init() {
// Set the clock frequency
clock_.SetFrequency(kApuClockSpeed);
// Initialize Digital Signal Processor Callbacks
dsp_.SetSampleFetcher([this](uint16_t address) -> uint8_t {
return this->FetchSampleFromRam(address);
});
dsp_.SetSamplePusher(
[this](int16_t sample) { this->PushToAudioBuffer(sample); });
}
void APU::Reset() {
clock_.ResetAccumulatedTime();
spc700_.Reset();
dsp_.Reset();
}
void APU::Update() {
auto cycles_to_run = clock_.GetCycleCount();
for (auto i = 0; i < cycles_to_run; ++i) {
// Update the APU
UpdateChannelSettings();
// Update the SPC700
uint8_t opcode = spc700_.read(spc700_.PC);
spc700_.ExecuteInstructions(opcode);
spc700_.PC++;
}
ProcessSamples();
}
void APU::Notify(uint32_t address, uint8_t data) {
if (address < 0x2140 || address > 0x2143) {
return;
}
auto offset = address - 0x2140;
spc700_.write(offset, data);
// HACK - This is a temporary solution to get the APU to play audio
ports_[address - 0x2140] = data;
switch (address) {
case 0x2140:
if (data == BEGIN_SIGNAL) {
SignalReady();
}
break;
case 0x2141:
// TODO: Handle data byte transfer here
break;
case 0x2142:
// TODO: Handle the setup of destination address
break;
case 0x2143:
// TODO: Handle additional communication/commands
break;
}
}
void APU::ProcessSamples() {
// Fetch sample data from AudioRam
// Iterate over all voices
for (uint8_t voice_num = 0; voice_num < 8; voice_num++) {
// Fetch the sample data for the current voice from AudioRam
uint8_t sample = FetchSampleForVoice(voice_num);
// Process the sample through DSP
int16_t processed_sample = dsp_.ProcessSample(voice_num, sample);
// Add the processed sample to the audio buffer
audio_samples_.push_back(processed_sample);
}
}
uint8_t APU::FetchSampleForVoice(uint8_t voice_num) {
uint16_t address = CalculateAddressForVoice(voice_num);
return aram_.read(address);
}
uint16_t APU::CalculateAddressForVoice(uint8_t voice_num) {
// TODO: Calculate the address for the specified voice
return voice_num;
}
int16_t APU::GetNextSample() {
if (!audio_samples_.empty()) {
int16_t sample = audio_samples_.front();
audio_samples_.erase(audio_samples_.begin());
return sample;
}
return 0; // TODO: Return the last sample instead of 0.
}
const std::vector<int16_t>& APU::GetAudioSamples() const {
return audio_samples_;
}
void APU::UpdateChannelSettings() {
// TODO: Implement this method to update the channel settings.
}
int16_t APU::GenerateSample(int channel) {
// TODO: Implement this method to generate a sample for the specified channel.
}
void APU::ApplyEnvelope(int channel) {
// TODO: Implement this method to apply an envelope to the specified channel.
}
uint8_t APU::ReadDspMemory(uint16_t address) {
return dsp_.ReadGlobalReg(address);
}
void APU::WriteDspMemory(uint16_t address, uint8_t value) {
dsp_.WriteGlobalReg(address, value);
}
} // namespace emu
} // namespace app
} // namespace yaze