From e28ad1546509de31b706f0fd300a906e5bc55199 Mon Sep 17 00:00:00 2001 From: Peter Fors Date: Thu, 8 May 2025 21:03:43 +0200 Subject: new and changed mappers --- mappers/mapper_003_1.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 mappers/mapper_003_1.c (limited to 'mappers/mapper_003_1.c') diff --git a/mappers/mapper_003_1.c b/mappers/mapper_003_1.c new file mode 100644 index 0000000..fd7cd27 --- /dev/null +++ b/mappers/mapper_003_1.c @@ -0,0 +1,31 @@ + +__attribute__((section(".mapper_003_1"), hot)) +static uint8_t mapper_003_1_prg_read(struct nes_state *state, uint32_t addr) { + return state->prg_rom[addr & 0x7fff]; +} + +__attribute__((section(".mapper_003_1"), hot)) +static void mapper_003_1_prg_write(struct nes_state *state, uint32_t addr, uint8_t value) { + struct mapper_003_1 *mapper = (struct mapper_003_1 *)&state->map; + + if(addr >= 0x8000) { + mapper->chr_ptr = state->chr_rom + (value & 3) * 0x2000; + } +} + +__attribute__((section(".mapper_003_1"), hot)) +static uint8_t mapper_003_1_chr_read(struct nes_state *state, uint32_t addr) { + struct mapper_003_1 *mapper = (struct mapper_003_1 *)&state->map; + return mapper->chr_ptr[addr]; +} + +__attribute__((section(".mapper_003_1"))) +static void mapper_003_1_init(struct nes_state *state) { + struct mapper_003_1 *mapper = (struct mapper_003_1 *)&state->map; + + mapper->chr_ptr = state->chr_rom; + + state->mapper.prg_read = mapper_003_1_prg_read; + state->mapper.prg_write = mapper_003_1_prg_write; + state->mapper.chr_read = mapper_003_1_chr_read; +} -- cgit v1.2.3