BizHawk/libsnes/bsnes/snes/chip/hitachidsp/hitachidsp.cpp

88 lines
1.9 KiB
C++

#include <snes/snes.hpp>
#define HITACHIDSP_CPP
namespace SNES {
#include "memory.cpp"
#include "opcodes.cpp"
#include "registers.cpp"
#include "serialization.cpp"
HitachiDSP hitachidsp;
//zero 01-sep-2014 - dont clobber these when reconstructing!
unsigned HitachiDSP::frequency;
uint24 HitachiDSP::dataROM[1024];
void HitachiDSP::Enter() { hitachidsp.enter(); }
void HitachiDSP::enter() {
while(true) {
// exit requested due to savestate
if(scheduler.sync == Scheduler::SynchronizeMode::All) {
scheduler.exit(Scheduler::ExitReason::SynchronizeEvent);
}
// if we bail out due to savestating, the first thing we'll try afterwards is synchronize_cpu() again
synchronize_cpu();
switch(state) {
case State::Idle:
step(1);
break;
case State::DMA:
for(unsigned n = 0; n < regs.dma_length; n++) {
bus.write(regs.dma_target + n, bus.read(regs.dma_source + n));
step(2);
}
state = State::Idle;
break;
case State::Execute:
unsigned offset = regs.program_offset + regs.pc * 2;
opcode = bus_read(offset + 0) << 0;
opcode |= bus_read(offset + 1) << 8;
regs.pc = (regs.pc & 0xffff00) | ((regs.pc + 1) & 0x0000ff);
exec();
step(1);
break;
}
// this call is gone, but it's the first thing we try at the top of the loop AFTER we bail out
//synchronize_cpu();
}
}
void HitachiDSP::init() {
}
void HitachiDSP::load() {
}
void HitachiDSP::unload() {
}
void HitachiDSP::power() {
}
void HitachiDSP::reset() {
create(HitachiDSP::Enter, frequency);
state = State::Idle;
regs.n = 0;
regs.z = 0;
regs.c = 0;
regs.dma_source = 0x000000;
regs.dma_length = 0x0000;
regs.dma_target = 0x000000;
regs.r1f48 = 0x00;
regs.program_offset = 0x000000;
regs.r1f4c = 0x00;
regs.page_number = 0x0000;
regs.program_counter = 0x00;
regs.r1f50 = 0x33;
regs.r1f51 = 0x00;
regs.r1f52 = 0x01;
}
}