bsnes/higan/md/vdp/vdp.cpp

85 lines
1.7 KiB
C++

#include <md/md.hpp>
namespace MegaDrive {
VDP vdp;
#include "memory.cpp"
#include "io.cpp"
#include "dma.cpp"
#include "render.cpp"
#include "background.cpp"
#include "sprite.cpp"
#include "serialization.cpp"
auto VDP::Enter() -> void {
while(true) scheduler.synchronize(), vdp.main();
}
auto VDP::main() -> void {
scanline();
cpu.lower(CPU::Interrupt::HorizontalBlank);
apu.setINT(false);
if(state.vcounter == 0) {
latch.horizontalInterruptCounter = io.horizontalInterruptCounter;
cpu.lower(CPU::Interrupt::VerticalBlank);
}
if(state.vcounter == screenHeight()) {
if(io.verticalBlankInterruptEnable) {
cpu.raise(CPU::Interrupt::VerticalBlank);
}
//todo: should only stay high for ~2573/2 clocks
apu.setINT(true);
}
if(state.vcounter < screenHeight()) {
while(state.hcounter < 1280) {
run();
step(pixelWidth());
}
if(latch.horizontalInterruptCounter-- == 0) {
latch.horizontalInterruptCounter = io.horizontalInterruptCounter;
if(io.horizontalBlankInterruptEnable) {
cpu.raise(CPU::Interrupt::HorizontalBlank);
}
}
step(430);
} else {
step(1710);
}
}
auto VDP::step(uint clocks) -> void {
state.hcounter += clocks;
while(clocks--) {
dma.run();
Thread::step(1);
synchronize(cpu);
synchronize(apu);
}
}
auto VDP::refresh() -> void {
Emulator::video.refresh(buffer, 1280 * sizeof(uint32), 1280, 480);
}
auto VDP::power() -> void {
create(VDP::Enter, system.frequency() / 2.0);
memory::fill(&io, sizeof(IO));
memory::fill(&latch, sizeof(Latch));
memory::fill(&state, sizeof(State));
planeA.power();
window.power();
planeB.power();
sprite.power();
dma.power();
}
}