//BANDAI-FCG struct BandaiFCG : Board { uint8 chr_bank[8]; uint8 prg_bank; uint2 mirror; bool irq_counter_enable; uint16 irq_counter; uint16 irq_latch; void main() { while(true) { if(scheduler.sync == Scheduler::SynchronizeMode::All) { scheduler.exit(Scheduler::ExitReason::SynchronizeEvent); } if(irq_counter_enable) { if(--irq_counter == 0xffff) { cpu.set_irq_line(1); irq_counter_enable = false; } } tick(); } } unsigned ciram_addr(unsigned addr) const { switch(mirror) { case 0: return ((addr & 0x0400) >> 0) | (addr & 0x03ff); case 1: return ((addr & 0x0800) >> 1) | (addr & 0x03ff); case 2: return 0x0000 | (addr & 0x03ff); case 3: return 0x0400 | (addr & 0x03ff); } } uint8 prg_read(unsigned addr) { if(addr & 0x8000) { bool region = addr & 0x4000; unsigned bank = (region == 0 ? prg_bank : 0x0f); return prgrom.read((bank << 14) | (addr & 0x3fff)); } return cpu.mdr(); } void prg_write(unsigned addr, uint8 data) { if(addr >= 0x6000) { switch(addr & 15) { case 0x00: case 0x01: case 0x02: case 0x03: case 0x04: case 0x05: case 0x06: case 0x07: chr_bank[addr & 7] = data; break; case 0x08: prg_bank = data & 0x0f; break; case 0x09: mirror = data & 0x03; break; case 0x0a: cpu.set_irq_line(0); irq_counter_enable = data & 0x01; irq_counter = irq_latch; break; case 0x0b: irq_latch = (irq_latch & 0xff00) | (data << 0); break; case 0x0c: irq_latch = (irq_latch & 0x00ff) | (data << 8); break; case 0x0d: //TODO: serial EEPROM support break; } } } uint8 chr_read(unsigned addr) { if(addr & 0x2000) return ppu.ciram_read(ciram_addr(addr)); addr = (chr_bank[addr >> 10] << 10) | (addr & 0x03ff); return Board::chr_read(addr); } void chr_write(unsigned addr, uint8 data) { if(addr & 0x2000) return ppu.ciram_write(ciram_addr(addr), data); addr = (chr_bank[addr >> 10] << 10) | (addr & 0x03ff); return Board::chr_write(addr, data); } void power() { reset(); } void reset() { for(auto &n : chr_bank) n = 0; prg_bank = 0; mirror = 0; irq_counter_enable = 0; irq_counter = 0; irq_latch = 0; } void serialize(serializer &s) { Board::serialize(s); s.array(chr_bank); s.integer(prg_bank); s.integer(mirror); s.integer(irq_counter_enable); s.integer(irq_counter); s.integer(irq_latch); } BandaiFCG(Markup::Node &document) : Board(document) { } };