bsnes/higan/md/cartridge/cartridge.cpp

128 lines
3.6 KiB
C++

#include <md/md.hpp>
namespace MegaDrive {
Cartridge cartridge;
#include "serialization.cpp"
auto Cartridge::load() -> bool {
information = {};
if(auto loaded = platform->load(ID::MegaDrive, "Mega Drive", "md", {"Auto", "NTSC-J", "NTSC-U", "PAL"})) {
information.pathID = loaded.pathID();
information.region = loaded.option();
} else return false;
if(auto fp = platform->open(pathID(), "manifest.bml", File::Read, File::Required)) {
information.manifest = fp->reads();
} else return false;
auto document = BML::unserialize(information.manifest);
information.title = document["information/title"].text();
if(information.region == "Auto") {
if(auto region = document["board/region"].text()) {
information.region = region.upcase();
} else {
information.region = "NTSC-J";
}
}
if(auto node = document["board/rom"]) {
rom.size = node["size"].natural() >> 1;
rom.mask = bit::round(rom.size) - 1;
if(rom.size) {
rom.data = new uint16[rom.mask + 1]();
if(auto name = node["name"].text()) {
if(auto fp = platform->open(pathID(), name, File::Read, File::Required)) {
for(uint n : range(rom.size)) rom.data[n] = fp->readm(2);
}
}
}
}
if(auto node = document["board/ram"]) {
if(auto mode = node["mode"].text()) {
if(mode == "lo" ) ram.bits = 0x00ff;
if(mode == "hi" ) ram.bits = 0xff00;
if(mode == "word") ram.bits = 0xffff;
}
ram.size = node["size"].natural() >> (ram.bits == 0xffff);
ram.mask = bit::round(ram.size) - 1;
if(ram.size) {
ram.data = new uint16[ram.mask + 1]();
if(auto name = node["name"].text()) {
if(auto fp = platform->open(pathID(), name, File::Read)) {
for(uint n : range(ram.size)) {
if(ram.bits != 0xffff) ram.data[n] = fp->readm(1) * 0x0101;
if(ram.bits == 0xffff) ram.data[n] = fp->readm(2);
}
}
}
}
}
return true;
}
auto Cartridge::save() -> void {
auto document = BML::unserialize(information.manifest);
if(auto name = document["board/ram/name"].text()) {
if(auto fp = platform->open(pathID(), name, File::Write)) {
for(uint n : range(ram.size)) {
if(ram.bits != 0xffff) fp->writem(ram.data[n], 1);
if(ram.bits == 0xffff) fp->writem(ram.data[n], 2);
}
}
}
}
auto Cartridge::unload() -> void {
delete[] rom.data;
delete[] ram.data;
rom = {};
ram = {};
}
auto Cartridge::power() -> void {
ramEnable = 1;
ramWritable = 1;
for(auto n : range(8)) bank[n] = n;
}
auto Cartridge::read(uint24 address) -> uint16 {
if(address.bit(21) && ram.size && ramEnable) {
return ram.data[address >> 1 & ram.mask];
} else {
address = bank[address.bits(19,21)] << 19 | address.bits(0,18);
return rom.data[address >> 1 & rom.mask];
}
}
auto Cartridge::write(uint24 address, uint16 data) -> void {
//emulating RAM write protect bit breaks some commercial software
if(address.bit(21) && ram.size && ramEnable /* && ramWritable */) {
if(ram.bits == 0x00ff) data = data.byte(0) * 0x0101;
if(ram.bits == 0xff00) data = data.byte(1) * 0x0101;
ram.data[address >> 1 & ram.mask] = data;
}
}
auto Cartridge::readIO(uint24 addr) -> uint16 {
return 0x0000;
}
auto Cartridge::writeIO(uint24 addr, uint16 data) -> void {
if(addr == 0xa130f1) ramEnable = data.bit(0), ramWritable = data.bit(1);
if(addr == 0xa130f3) bank[1] = data;
if(addr == 0xa130f5) bank[2] = data;
if(addr == 0xa130f7) bank[3] = data;
if(addr == 0xa130f9) bank[4] = data;
if(addr == 0xa130fb) bank[5] = data;
if(addr == 0xa130fd) bank[6] = data;
if(addr == 0xa130ff) bank[7] = data;
}
}