ShuriZma
/
bsnes
mirror of https://github.com/bsnes-emu/bsnes.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
bsnes/gba/apu/square1.cpp

105 lines
2.5 KiB
C++
Raw Normal View History

Update to v087r17 release. byuu says: Emulated GBC sound plus the new extensions to it. I am kind of surprised by how little developers utilized the GBC audio portion. Mr. Driller now has sound effects, and Pinobee no Daibouken has BGM. I still have yet to emulate the GBA extra sound channels and PWM. Need to emulate timers and DMA 2 refresh mode before I can do that. Also, I moved both GBC and GBA audio to use length = data; if(++length == 0); rather than length = 64 - data; if(--length == 0); so that I could return literal values for register reads. I thought there was a good reason we used the latter version, but I can't hear any audible difference even in GBC games, so oh well. Lastly, I think the pattern[++offset] in the wave channel was a bug in the DMG/GBC only. I really, really hope it doesn't apply to the GBA, because that will make bank selection a serious pain in the ass.
2012-04-06 04:29:50 +00:00
void APU::Square1::runsweep(bool update) {
if(sweep.enable == false) return;
sweep.negate = sweep.direction;
unsigned delta = shadowfrequency >> sweep.shift;
signed updatefrequency = shadowfrequency + (sweep.negate ? -delta : delta);
if(updatefrequency > 2047) {
enable = false;
} else if(sweep.shift && update) {
shadowfrequency = updatefrequency;
frequency = updatefrequency;
Update to v093r07 release. byuu says: Changelog: - importing a game won't show message box on success - importing a game will select the game that was imported in the list - caveat: GTK+ port doesn't seem to be removing focus from item 0 even though the selection is on item 2 - Game Boy audio reduced in volume by 50% - Game Boy Advance audio reduced in volume by 50% - Game Boy internally mixes audio at 2MHz now - Game Boy Advance's Game Boy audio hardware internally mixes audio at 2MHz now - Game Boy Color doesn't sort sprites by X-coordinate - Game Boy Color allows transparency on BGpriority pixels - caveat: this seems to allow sprites to appear on top of windows - Game Boy Color VRAM DMA transfers 16 bytes in 8 clocks (or 16 clocks in double speed mode) - Game Boy Color VRAM DMA masks low 4-bits of source and destination address - Game Boy Color VRAM DMA only allows reads from ROM or RAM - Game Boy Color VRAM DMA only allows writes to VRAM - fixed a bug in dereferencing a nullptr from pObject::find(), should fix crash when pressing enter key on blank windows - fixed Windows RadioItem selection - Game Boy Advance color emulation code added
2013-12-10 12:12:54 +00:00
period = 2 * (2048 - frequency);
Update to v087r17 release. byuu says: Emulated GBC sound plus the new extensions to it. I am kind of surprised by how little developers utilized the GBC audio portion. Mr. Driller now has sound effects, and Pinobee no Daibouken has BGM. I still have yet to emulate the GBA extra sound channels and PWM. Need to emulate timers and DMA 2 refresh mode before I can do that. Also, I moved both GBC and GBA audio to use length = data; if(++length == 0); rather than length = 64 - data; if(--length == 0); so that I could return literal values for register reads. I thought there was a good reason we used the latter version, but I can't hear any audible difference even in GBC games, so oh well. Lastly, I think the pattern[++offset] in the wave channel was a bug in the DMG/GBC only. I really, really hope it doesn't apply to the GBA, because that will make bank selection a serious pain in the ass.
2012-04-06 04:29:50 +00:00
}
}
void APU::Square1::clocksweep() {
if(enable && sweep.frequency && --sweep.period == 0) {
sweep.period = sweep.frequency;
runsweep(1);
runsweep(0);
}
}
uint8 APU::Square1::read(unsigned addr) const {
switch(addr) {
case 0: return (sweep.shift << 0) | (sweep.direction << 3) | (sweep.frequency << 4);
case 1: return (length << 0) | (duty << 6);
case 2: return (envelope.frequency << 0) | (envelope.direction << 3) | (envelope.volume << 4);
case 3: return (frequency << 0);
case 4: return (frequency >> 8) | (counter << 6) | (initialize << 7);
}
}
void APU::Square1::write(unsigned addr, uint8 byte) {
switch(addr) {
case 0: //NR10
if(sweep.negate && sweep.direction && !(byte & 0x08)) enable = false;
sweep.shift = byte >> 0;
sweep.direction = byte >> 3;
sweep.frequency = byte >> 4;
break;
case 1: //NR11
length = byte >> 0;
duty = byte >> 6;
break;
case 2: //NR12
envelope.frequency = byte >> 0;
envelope.direction = byte >> 3;
envelope.volume = byte >> 4;
if(envelope.dacenable() == false) enable = false;
break;
case 3: //NR13
frequency = (frequency & 0xff00) | (byte << 0);
break;
case 4: //NR14
frequency = (frequency & 0x00ff) | (byte << 8);
counter = byte >> 6;
initialize = byte >> 7;
if(initialize) {
enable = envelope.dacenable();
Update to v093r07 release. byuu says: Changelog: - importing a game won't show message box on success - importing a game will select the game that was imported in the list - caveat: GTK+ port doesn't seem to be removing focus from item 0 even though the selection is on item 2 - Game Boy audio reduced in volume by 50% - Game Boy Advance audio reduced in volume by 50% - Game Boy internally mixes audio at 2MHz now - Game Boy Advance's Game Boy audio hardware internally mixes audio at 2MHz now - Game Boy Color doesn't sort sprites by X-coordinate - Game Boy Color allows transparency on BGpriority pixels - caveat: this seems to allow sprites to appear on top of windows - Game Boy Color VRAM DMA transfers 16 bytes in 8 clocks (or 16 clocks in double speed mode) - Game Boy Color VRAM DMA masks low 4-bits of source and destination address - Game Boy Color VRAM DMA only allows reads from ROM or RAM - Game Boy Color VRAM DMA only allows writes to VRAM - fixed a bug in dereferencing a nullptr from pObject::find(), should fix crash when pressing enter key on blank windows - fixed Windows RadioItem selection - Game Boy Advance color emulation code added
2013-12-10 12:12:54 +00:00
period = 2 * (2048 - frequency);
Update to v087r17 release. byuu says: Emulated GBC sound plus the new extensions to it. I am kind of surprised by how little developers utilized the GBC audio portion. Mr. Driller now has sound effects, and Pinobee no Daibouken has BGM. I still have yet to emulate the GBA extra sound channels and PWM. Need to emulate timers and DMA 2 refresh mode before I can do that. Also, I moved both GBC and GBA audio to use length = data; if(++length == 0); rather than length = 64 - data; if(--length == 0); so that I could return literal values for register reads. I thought there was a good reason we used the latter version, but I can't hear any audible difference even in GBC games, so oh well. Lastly, I think the pattern[++offset] in the wave channel was a bug in the DMG/GBC only. I really, really hope it doesn't apply to the GBA, because that will make bank selection a serious pain in the ass.
2012-04-06 04:29:50 +00:00
envelope.period = envelope.frequency;
volume = envelope.volume;
shadowfrequency = frequency;
sweep.period = sweep.frequency;
sweep.enable = sweep.period || sweep.shift;
sweep.negate = false;
if(sweep.shift) runsweep(0);
}
break;
}
}
void APU::Square1::power() {
envelope.frequency = 0;
envelope.direction = 0;
envelope.direction = 0;
envelope.period = 0;
sweep.shift = 0;
sweep.direction = 0;
sweep.frequency = 0;
sweep.enable = 0;
sweep.negate = 0;
sweep.period = 0;
enable = 0;
length = 0;
duty = 0;
frequency = 0;
counter = 0;
initialize = 0;
shadowfrequency = 0;
signal = 0;
output = 0;
period = 0;
phase = 0;
volume = 0;
}