//NES-BN-ROM-01 struct NES_BNROM : Board { NES_BNROM(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((prg_bank << 15) | (addr & 0x7fff)); return cpu.mdr(); } auto prg_write(uint addr, uint8 data) -> void { if(addr & 0x8000) prg_bank = data & 0x03; } auto chr_read(uint addr) -> uint8 { if(addr & 0x2000) { if(settings.mirror == 0) addr = ((addr & 0x0800) >> 1) | (addr & 0x03ff); return ppu.ciram_read(addr); } return Board::chr_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, data); } return Board::chr_write(addr, data); } auto power() -> void { } auto reset() -> void { prg_bank = 0; } auto serialize(serializer& s) -> void { Board::serialize(s); s.integer(prg_bank); } struct Settings { bool mirror; //0 = horizontal, 1 = vertical } settings; uint2 prg_bank; };