mapper_2002.c


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static void mapper_2002_init(struct nes_state *state) {
	state->map.m2002.prg_bank0 = state->prg_rom; // default to bank 0
	state->map.m2002.prg_bank1 = state->prg_rom + state->ines.prg_size - 0x4000;
}

static uint8_t mapper_2002_prg_read(struct nes_state *state, uint32_t addr) {
	if(addr >= 0x8000 && addr < 0xc000) {
		return state->map.m2002.prg_bank0[addr & 0x3fff];
	} else if(addr >= 0xc000) {
		return state->map.m2002.prg_bank1[addr & 0x3fff];
	}
	return 0;
}

static void mapper_2002_prg_write(struct nes_state *state, uint32_t addr, uint8_t value) {
	if(addr >= 0x8000) {
		state->map.m2002.prg_bank0 = state->prg_rom + ((value & 0x0f) * 0x4000);
	}
}

static uint8_t mapper_2002_chr_read(struct nes_state *state, uint32_t addr) {
	return state->chr_ram[addr];
}

static void mapper_2002_chr_write(struct nes_state *state, uint32_t addr, uint8_t value) {
	state->chr_ram[addr] = value;
}