///////////////////////////////////////////////////////////////////// // Mapper 44 void NES_mapper44::Reset() { // clear registers FIRST!!! for(int i = 0; i < 8; i++) regs[i] = 0x00; // set game select register rom_bank = 0; // set CPU bank pointers prg0 = 0; prg1 = 1; MMC3_set_CPU_banks(); // set VROM banks if(num_1k_VROM_banks) { chr01 = 0; chr23 = 2; chr4 = 4; chr5 = 5; chr6 = 6; chr7 = 7; MMC3_set_PPU_banks(); } else { chr01 = chr23 = chr4 = chr5 = chr6 = chr7 = 0; } irq_enabled = 0; irq_counter = 0; irq_latch = 0; } void NES_mapper44::MemoryWrite(uint32 addr, uint8 data) { switch(addr & 0xE001) { case 0x8000: { regs[0] = data; MMC3_set_PPU_banks(); MMC3_set_CPU_banks(); } break; case 0x8001: { uint32 bank_num; regs[1] = data; bank_num = regs[1]; switch(regs[0] & 0x07) { case 0x00: { if(num_1k_VROM_banks) { bank_num &= 0xfe; chr01 = bank_num; MMC3_set_PPU_banks(); } } break; case 0x01: { if(num_1k_VROM_banks) { bank_num &= 0xfe; chr23 = bank_num; MMC3_set_PPU_banks(); } } break; case 0x02: { if(num_1k_VROM_banks) { chr4 = bank_num; MMC3_set_PPU_banks(); } } break; case 0x03: { if(num_1k_VROM_banks) { chr5 = bank_num; MMC3_set_PPU_banks(); } } break; case 0x04: { if(num_1k_VROM_banks) { chr6 = bank_num; MMC3_set_PPU_banks(); } } break; case 0x05: { if(num_1k_VROM_banks) { chr7 = bank_num; MMC3_set_PPU_banks(); } } break; case 0x06: { prg0 = bank_num; MMC3_set_CPU_banks(); } break; case 0x07: { prg1 = bank_num; MMC3_set_CPU_banks(); } break; } } break; case 0xA000: { regs[2] = data; if(parent_NES->ROM->get_mirroring() != NES_PPU::MIRROR_FOUR_SCREEN) { if(data & 0x01) { set_mirroring(NES_PPU::MIRROR_HORIZ); } else { set_mirroring(NES_PPU::MIRROR_VERT); } } } break; case 0xA001: { rom_bank = data & 0x07; if(rom_bank == 7) { rom_bank = 6; } MMC3_set_CPU_banks(); MMC3_set_PPU_banks(); } break; case 0xC000: regs[4] = data; irq_counter = regs[4]; break; case 0xC001: regs[5] = data; irq_latch = regs[5]; break; case 0xE000: regs[6] = data; irq_enabled = 0; break; case 0xE001: regs[7] = data; irq_enabled = 1; break; } } void NES_mapper44::HSync(uint32 scanline) { if(irq_enabled) { if((scanline >= 0) && (scanline <= 239)) { if(parent_NES->ppu->spr_enabled() || parent_NES->ppu->bg_enabled()) { if(!(irq_counter--)) { irq_counter = irq_latch; parent_NES->cpu->DoIRQ(); } } } } } void NES_mapper44::MMC3_set_CPU_banks() { if(prg_swap()) { set_CPU_bank4(((rom_bank == 6) ? 0x1e : 0x0e) | (rom_bank << 4)); set_CPU_bank5(((rom_bank == 6) ? 0x1f & prg1 : 0x0f & prg1) | (rom_bank << 4)); set_CPU_bank6(((rom_bank == 6) ? 0x1f & prg0 : 0x0f & prg0) | (rom_bank << 4)); set_CPU_bank7(((rom_bank == 6) ? 0x1f : 0x0f) | (rom_bank << 4)); } else { set_CPU_bank4(((rom_bank == 6) ? 0x1f & prg0: 0x0f & prg0) | (rom_bank << 4)); set_CPU_bank5(((rom_bank == 6) ? 0x1f & prg1: 0x0f & prg1) | (rom_bank << 4)); set_CPU_bank6(((rom_bank == 6) ? 0x1e : 0x0e) | (rom_bank << 4)); set_CPU_bank7(((rom_bank == 6) ? 0x1f : 0x0f) | (rom_bank << 4)); } } void NES_mapper44::MMC3_set_PPU_banks() { if(num_1k_VROM_banks) { if(chr_swap()) { set_PPU_bank0(((rom_bank == 6) ? 0xff & chr4 : 0x7f & chr4) | (rom_bank << 7)); set_PPU_bank1(((rom_bank == 6) ? 0xff & chr5 : 0x7f & chr5) | (rom_bank << 7)); set_PPU_bank2(((rom_bank == 6) ? 0xff & chr6 : 0x7f & chr6) | (rom_bank << 7)); set_PPU_bank3(((rom_bank == 6) ? 0xff & chr7 : 0x7f & chr7) | (rom_bank << 7)); set_PPU_bank4(((rom_bank == 6) ? 0xff & chr01 : 0x7f & chr01) | (rom_bank << 7)); set_PPU_bank5(((rom_bank == 6) ? 0xff & (chr01+1) : 0x7f & (chr01+1)) | (rom_bank << 7)); set_PPU_bank6(((rom_bank == 6) ? 0xff & chr23: 0x7f & chr23) | (rom_bank << 7)); set_PPU_bank7(((rom_bank == 6) ? 0xff & (chr23+1) : 0x7f & (chr23+1)) | (rom_bank << 7)); } else { set_PPU_bank0(((rom_bank == 6) ? 0xff & chr01 : 0x7f & chr01) | (rom_bank << 7)); set_PPU_bank1(((rom_bank == 6) ? 0xff & (chr01+1) : 0x7f & (chr01+1)) | (rom_bank << 7)); set_PPU_bank2(((rom_bank == 6) ? 0xff & chr23: 0x7f & chr23) | (rom_bank << 7)); set_PPU_bank3(((rom_bank == 6) ? 0xff & (chr23+1) : 0x7f & (chr23+1)) | (rom_bank << 7)); set_PPU_bank4(((rom_bank == 6) ? 0xff & chr4 : 0x7f & chr4) | (rom_bank << 7)); set_PPU_bank5(((rom_bank == 6) ? 0xff & chr5 : 0x7f & chr5) | (rom_bank << 7)); set_PPU_bank6(((rom_bank == 6) ? 0xff & chr6 : 0x7f & chr6) | (rom_bank << 7)); set_PPU_bank7(((rom_bank == 6) ? 0xff & chr7 : 0x7f & chr7) | (rom_bank << 7)); } } } /////////////////////////////////////////////////////////////////////