bsnes/higan/sfc/expansion/21fx/21fx.cpp

135 lines
2.8 KiB
C++

#include <sfc/sfc.hpp>
namespace SuperFamicom {
S21FX s21fx;
auto S21FX::Enter() -> void {
while(true) scheduler.synchronize(), s21fx.main();
}
auto S21FX::main() -> void {
if(linkInit) linkInit(
{&S21FX::quit, this},
{&S21FX::usleep, this},
{&S21FX::readable, this},
{&S21FX::writable, this},
{&S21FX::read, this},
{&S21FX::write, this}
);
if(linkMain) linkMain({});
while(true) step(10'000'000);
}
auto S21FX::init() -> void {
}
auto S21FX::load() -> void {
resetVector.byte(0) = bus.read(0xfffc, 0x00);
resetVector.byte(1) = bus.read(0xfffd, 0x00);
for(auto& byte : ram) byte = 0xdb; //stp
ram[0] = 0x6c; //jmp ($fffc)
ram[1] = 0xfc;
ram[2] = 0xff;
bus.map({&S21FX::read, &s21fx}, {&S21FX::write, &s21fx}, 0x00, 0x00, 0xfffc, 0xfffd);
bus.map({&S21FX::read, &s21fx}, {&S21FX::write, &s21fx}, 0x00, 0x3f, 0x2184, 0x21ff);
bus.map({&S21FX::read, &s21fx}, {&S21FX::write, &s21fx}, 0x80, 0xbf, 0x2184, 0x21ff);
if(auto buffer = file::read({interface->path(ID::System), "21fx.rom"})) {
memory::copy(ram, sizeof(ram), buffer.data(), buffer.size());
}
string filename{interface->path(ID::SuperFamicom), "21fx.so"};
if(link.openAbsolute(filename)) {
linkInit = link.sym("fx_init");
linkMain = link.sym("fx_main");
}
}
auto S21FX::unload() -> void {
if(link.open()) link.close();
linkInit.reset();
linkMain.reset();
}
auto S21FX::power() -> void {
}
auto S21FX::reset() -> void {
create(S21FX::Enter, 10'000'000);
booted = false;
}
auto S21FX::read(uint24 addr, uint8 data) -> uint8 {
addr &= 0x40ffff;
if(addr == 0xfffc) return booted ? resetVector.byte(0) : (uint8)0x84;
if(addr == 0xfffd) return booted ? resetVector.byte(1) : (booted = true, (uint8)0x21);
if(addr >= 0x2184 && addr <= 0x21fd) return ram[addr - 0x2184];
if(addr == 0x21fe) return (
(linkBuffer.size() > 0) << 7 //1 = readable
| (snesBuffer.size() < 65536) << 6 //1 = writable
| (link.open()) << 5 //1 = connected
);
if(addr == 0x21ff) {
if(linkBuffer.size() > 0) {
data = linkBuffer.takeFirst();
}
}
return data;
}
auto S21FX::write(uint24 addr, uint8 data) -> void {
addr &= 0x40ffff;
if(addr == 0x21ff) {
if(snesBuffer.size() < 65536) {
snesBuffer.append(data);
}
}
}
auto S21FX::quit() -> bool {
step(1);
return false;
}
auto S21FX::usleep(uint microseconds) -> void {
step(10 * microseconds);
}
auto S21FX::readable() -> bool {
step(1);
return snesBuffer.size() > 0;
}
auto S21FX::writable() -> bool {
step(1);
return linkBuffer.size() < 65536;
}
//SNES -> Link
auto S21FX::read() -> uint8 {
step(1);
if(snesBuffer.size() > 0) {
return snesBuffer.takeFirst();
}
return 0x00;
}
//Link -> SNES
auto S21FX::write(uint8 data) -> void {
step(1);
if(linkBuffer.size() < 65536) {
linkBuffer.append(data);
}
}
}