summaryrefslogtreecommitdiff
path: root/memory.c
diff options
context:
space:
mode:
Diffstat (limited to 'memory.c')
-rw-r--r--memory.c16
1 files changed, 9 insertions, 7 deletions
diff --git a/memory.c b/memory.c
index 096189b..1eaf489 100644
--- a/memory.c
+++ b/memory.c
@@ -6,26 +6,28 @@ static inline uint8_t memory_read(struct nes_state *state, uint32_t offset) {
ppu_tick(state);
// apu_tick(state);
+ uint8_t result = 0;
+
if(offset >= 0x8000) { // MOST
- return state->mapper_function.prg_rom_read(state, offset);
+ result = state->mapper_function.prg_rom_read(state, offset);
- } else if((offset < 0x2000)) { // SECOND
- return state->ram[offset & 0x07ff];
+ } else if(offset < 0x2000) { // SECOND
+ result = state->ram[offset & 0x07ff];
} else if(offset < 0x4000) { // THIRD
- return ppu_read(state, offset);
+ result = ppu_read(state, offset);
} else if(offset >= 0x6000) {
- return state->mapper_function.prg_ram_read(state, offset);
+ result = state->mapper_function.prg_ram_read(state, offset);
} else if(offset == 0x4016 || offset == 0x4017) {
uint32_t index = offset & 1;
uint8_t value = (state->ppu.input_latch[index] >> state->ppu.input_bit[index]) & 1;
state->ppu.input_bit[index]++;
- return value | 0x40; // Bit 6 open bus high, bit 7 low
+ result = value | 0x40; // Bit 6 open bus high, bit 7 low
}
- return 0;
+ return result;
}
__attribute__((hot))