bsnes/fc/cpu/cpu.cpp

112 lines
2.2 KiB
C++

#include <fc/fc.hpp>
namespace Famicom {
#include "timing.cpp"
#include "serialization.cpp"
CPU cpu;
auto CPU::Enter() -> void {
while(true) {
if(scheduler.sync == Scheduler::SynchronizeMode::All) {
scheduler.exit(Scheduler::ExitReason::SynchronizeEvent);
}
cpu.main();
}
}
auto CPU::main() -> void {
if(status.interrupt_pending) {
interrupt();
return;
}
exec();
}
auto CPU::add_clocks(uint clocks) -> void {
apu.clock -= clocks;
if(apu.clock < 0 && scheduler.sync != Scheduler::SynchronizeMode::All) co_switch(apu.thread);
ppu.clock -= clocks;
if(ppu.clock < 0 && scheduler.sync != Scheduler::SynchronizeMode::All) co_switch(ppu.thread);
cartridge.clock -= clocks;
if(cartridge.clock < 0 && scheduler.sync != Scheduler::SynchronizeMode::All) co_switch(cartridge.thread);
}
auto CPU::power() -> void {
R6502::power();
for(auto addr : range(0x0800)) ram[addr] = 0xff;
ram[0x0008] = 0xf7;
ram[0x0009] = 0xef;
ram[0x000a] = 0xdf;
ram[0x000f] = 0xbf;
}
auto CPU::reset() -> void {
R6502::reset();
create(CPU::Enter, 21477272);
regs.pc = bus.read(0xfffc) << 0;
regs.pc |= bus.read(0xfffd) << 8;
status.interrupt_pending = false;
status.nmi_pending = false;
status.nmi_line = 0;
status.irq_line = 0;
status.irq_apu_line = 0;
status.rdy_line = 1;
status.rdy_addr_valid = false;
status.rdy_addr_value = 0x0000;
status.oam_dma_pending = false;
status.oam_dma_page = 0x00;
status.controller_latch = false;
status.controller_port0 = 0;
status.controller_port1 = 0;
}
auto CPU::debugger_read(uint16 addr) -> uint8 {
return bus.read(addr);
}
auto CPU::ram_read(uint16 addr) -> uint8 {
return ram[addr & 0x07ff];
}
auto CPU::ram_write(uint16 addr, uint8 data) -> void {
ram[addr & 0x07ff] = data;
}
auto CPU::read(uint16 addr) -> uint8 {
if(addr == 0x4016) {
return (mdr() & 0xc0) | input.data(0);
}
if(addr == 0x4017) {
return (mdr() & 0xc0) | input.data(1);
}
return apu.read(addr);
}
auto CPU::write(uint16 addr, uint8 data) -> void {
if(addr == 0x4014) {
status.oam_dma_page = data;
status.oam_dma_pending = true;
}
if(addr == 0x4016) {
input.latch(data & 0x01);
}
return apu.write(addr, data);
}
}