//NES-NROM-128 //NES-NROM-256 struct NES_NROM : Board { NES_NROM(Markup::Node& document) : Board(document) { settings.mirror = document["board/mirror/mode"].text() == "vertical" ? 1 : 0; } auto prg_read(uint addr) -> uint8 { if(addr & 0x8000) return prgrom.read(addr); return cpu.mdr(); } auto prg_write(uint addr, uint8 data) -> void { } auto chr_read(uint addr) -> uint8 { if(addr & 0x2000) { if(settings.mirror == 0) addr = ((addr & 0x0800) >> 1) | (addr & 0x03ff); return ppu.ciram_read(addr & 0x07ff); } if(chrram.size) return chrram.read(addr); return chrrom.read(addr); } auto chr_write(uint addr, uint8 data) -> void { if(addr & 0x2000) { if(settings.mirror == 0) addr = ((addr & 0x0800) >> 1) | (addr & 0x03ff); return ppu.ciram_write(addr & 0x07ff, data); } if(chrram.size) return chrram.write(addr, data); } auto serialize(serializer& s) -> void { Board::serialize(s); } struct Settings { bool mirror; //0 = horizontal, 1 = vertical } settings; };