From 6274071e3857c1640cc5aef804cb86509ab312f9 Mon Sep 17 00:00:00 2001 From: Peter Fors Date: Thu, 3 Apr 2025 20:02:00 +0200 Subject: Move to glfw --- mapper_066.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 mapper_066.c (limited to 'mapper_066.c') diff --git a/mapper_066.c b/mapper_066.c new file mode 100644 index 0000000..aabf471 --- /dev/null +++ b/mapper_066.c @@ -0,0 +1,27 @@ + +static void mapper_066_init(struct nes_state *state) { + state->map.m066.prg_offset = 0; + state->map.m066.chr_offset = 0; +} + +static uint8_t mapper_066_read(struct nes_state *state, uint32_t addr) { + if(addr >= 0x8000) { + uint32_t base = state->map.m066.prg_offset; + return state->rom[base + (addr - 0x8000)]; + } + return 0; +} + +static void mapper_066_write(struct nes_state *state, uint32_t addr, uint8_t value) { + if(addr >= 0x8000) { + uint32_t prg_bank = (value >> 4) & 3; + uint32_t chr_bank = (value >> 0) & 3; + + state->map.m066.prg_offset = prg_bank * 0x8000; + state->map.m066.chr_offset = chr_bank * 0x2000; + } +} + +static void mapper_066_tick(struct nes_state *state) { + // No IRQ or timing logic needed +} -- cgit v1.2.3