//NES-GNROM //NES-MHROM struct NES_GxROM : Board { NES_GxROM(Markup::Node& document) : Board(document) { settings.mirror = document["board/mirror/mode"].text() == "vertical" ? 1 : 0; } auto readPRG(uint addr) -> uint8 { if(addr & 0x8000) return prgrom.read((prgBank << 15) | (addr & 0x7fff)); return cpu.mdr(); } auto writePRG(uint addr, uint8 data) -> void { if(addr & 0x8000) { prgBank = (data & 0x30) >> 4; chrBank = (data & 0x03) >> 0; } } auto readCHR(uint addr) -> uint8 { if(addr & 0x2000) { if(settings.mirror == 0) addr = ((addr & 0x0800) >> 1) | (addr & 0x03ff); return ppu.readCIRAM(addr & 0x07ff); } addr = (chrBank * 0x2000) + (addr & 0x1fff); return Board::readCHR(addr); } auto writeCHR(uint addr, uint8 data) -> void { if(addr & 0x2000) { if(settings.mirror == 0) addr = ((addr & 0x0800) >> 1) | (addr & 0x03ff); return ppu.writeCIRAM(addr & 0x07ff, data); } addr = (chrBank * 0x2000) + (addr & 0x1fff); Board::writeCHR(addr, data); } auto power() -> void { } auto reset() -> void { prgBank = 0; chrBank = 0; } auto serialize(serializer& s) -> void { Board::serialize(s); s.integer(prgBank); s.integer(chrBank); } struct Settings { bool mirror; //0 = horizontal, 1 = vertical } settings; uint2 prgBank; uint2 chrBank; };