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-rw-r--r--mappers/mapper_066_0.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/mappers/mapper_066_0.c b/mappers/mapper_066_0.c
new file mode 100644
index 0000000..bf31720
--- /dev/null
+++ b/mappers/mapper_066_0.c
@@ -0,0 +1,38 @@
+
+static uint8_t mapper_066_0_prg_read(struct nes_state *state, uint32_t addr) {
+ struct mapper_066_0 *mapper = (struct mapper_066_0 *)&state->map;
+
+ if(addr >= 0x8000) {
+ return state->prg_rom[addr & 0x7fff];
+ }
+ return 0;
+}
+
+static void mapper_066_0_prg_write(struct nes_state *state, uint32_t addr, uint8_t value) {
+ struct mapper_066_0 *mapper = (struct mapper_066_0 *)&state->map;
+
+ if(addr >= 0x8000) {
+ uint32_t prg_bank = (value >> 4) & 3;
+ uint32_t chr_bank = (value >> 0) & 3;
+
+ mapper->prg_offset = state->prg_rom + (prg_bank * 0x8000);
+ mapper->chr_offset = state->chr_rom + (chr_bank * 0x2000);
+ }
+}
+
+static uint8_t mapper_066_0_chr_read(struct nes_state *state, uint32_t addr) {
+ struct mapper_066_0 *mapper = (struct mapper_066_0 *)&state->map;
+ return mapper->chr_offset[addr];
+}
+
+static void mapper_066_0_init(struct nes_state *state) {
+ struct mapper_066_0 *mapper = (struct mapper_066_0 *)&state->map;
+
+ mapper->prg_offset = state->prg_rom;
+ mapper->chr_offset = state->chr_rom;
+
+ state->mapper.prg_read = mapper_066_0_prg_read;
+ state->mapper.prg_write = mapper_066_0_prg_write;
+ state->mapper.chr_read = mapper_066_0_chr_read;
+}
+