//NES-GNROM //NES-MHROM struct NES_GxROM : Board { struct Settings { bool mirror; //0 = horizontal, 1 = vertical } settings; uint2 prg_bank; uint2 chr_bank; uint8 prg_read(unsigned addr) { if(addr & 0x8000) return prgrom.read((prg_bank << 15) | (addr & 0x7fff)); return cpu.mdr(); } void prg_write(unsigned addr, uint8 data) { if(addr & 0x8000) { prg_bank = (data & 0x30) >> 4; chr_bank = (data & 0x03) >> 0; } } uint8 chr_read(unsigned addr) { if(addr & 0x2000) { if(settings.mirror == 0) addr = ((addr & 0x0800) >> 1) | (addr & 0x03ff); return ppu.ciram_read(addr & 0x07ff); } addr = (chr_bank * 0x2000) + (addr & 0x1fff); return Board::chr_read(addr); } void chr_write(unsigned addr, uint8 data) { if(addr & 0x2000) { if(settings.mirror == 0) addr = ((addr & 0x0800) >> 1) | (addr & 0x03ff); return ppu.ciram_write(addr & 0x07ff, data); } addr = (chr_bank * 0x2000) + (addr & 0x1fff); Board::chr_write(addr, data); } void power() { } void reset() { prg_bank = 0; chr_bank = 0; } void serialize(serializer& s) { Board::serialize(s); s.integer(prg_bank); s.integer(chr_bank); } NES_GxROM(Markup::Node& document) : Board(document) { settings.mirror = document["cartridge/mirror/mode"].text() == "vertical" ? 1 : 0; } };