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Diffstat (limited to 'mappers/mapper_002_2.c')
-rw-r--r--mappers/mapper_002_2.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/mappers/mapper_002_2.c b/mappers/mapper_002_2.c
new file mode 100644
index 0000000..079fb0b
--- /dev/null
+++ b/mappers/mapper_002_2.c
@@ -0,0 +1,41 @@
+
+
+static uint8_t mapper_002_2_prg_read(struct nes_state *state, uint32_t addr) {
+ struct mapper_002_2 *mapper = (struct mapper_002_2 *)&state->map;
+
+ if(addr >= 0x8000 && addr < 0xc000) {
+ return mapper->prg_bank0[addr & 0x3fff];
+
+ } else if(addr >= 0xc000) {
+ return mapper->prg_bank1[addr & 0x3fff];
+ }
+ return 0;
+}
+
+static void mapper_002_2_prg_write(struct nes_state *state, uint32_t addr, uint8_t value) {
+ struct mapper_002_2 *mapper = (struct mapper_002_2 *)&state->map;
+
+ if(addr >= 0x8000) {
+ mapper->prg_bank0 = state->prg_rom + ((value & 0x0f) * 0x4000);
+ }
+}
+
+static uint8_t mapper_002_2_chr_read(struct nes_state *state, uint32_t addr) {
+ return state->chr_ram[addr];
+}
+
+static void mapper_002_2_chr_write(struct nes_state *state, uint32_t addr, uint8_t value) {
+ state->chr_ram[addr] = value;
+}
+
+static void mapper_002_2_init(struct nes_state *state) {
+ struct mapper_002_2 *mapper = (struct mapper_002_2 *)&state->map;
+
+ mapper->prg_bank0 = state->prg_rom;
+ mapper->prg_bank1 = state->prg_rom + state->ines.prg_size - 0x4000;
+
+ state->mapper.prg_read = mapper_002_2_prg_read;
+ state->mapper.prg_write = mapper_002_2_prg_write;
+ state->mapper.chr_read = mapper_002_2_chr_read;
+ state->mapper.chr_write = mapper_002_2_chr_write;
+}