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-rw-r--r--memory.c58
1 files changed, 43 insertions, 15 deletions
diff --git a/memory.c b/memory.c
index 1eaf489..db5fcd0 100644
--- a/memory.c
+++ b/memory.c
@@ -1,10 +1,46 @@
+#if 1
__attribute__((hot))
static inline uint8_t memory_read(struct nes_state *state, uint32_t offset) {
state->cpu.cycles++;
ppu_tick(state);
- // apu_tick(state);
+ apu_tick(state);
+
+ uint8_t result = 0;
+
+ if(offset >= 0x8000) { // MOST
+ result = state->mapper_function.prg_rom_read(state, offset);
+
+ } else if(offset < 0x2000) { // SECOND
+ result = state->ram[offset & 0x07ff];
+
+ } else if(offset < 0x4000) { // THIRD
+ result = ppu_read(state, offset);
+
+ } else if(offset == 0x4015) { // APU status
+ result = apu_read4015(state);
+
+ } 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]++;
+ result = value | 0x40; // Bit 6 open bus high, bit 7 low
+
+ } else if(offset >= 0x6000) {
+ result = state->mapper_function.prg_ram_read(state, offset);
+ }
+
+ return result;
+}
+
+#else
+
+__attribute__((hot))
+static inline uint8_t memory_read(struct nes_state *state, uint32_t offset) {
+ state->cpu.cycles++;
+ ppu_tick(state);
+ apu_tick(state);
uint8_t result = 0;
@@ -29,12 +65,13 @@ static inline uint8_t memory_read(struct nes_state *state, uint32_t offset) {
return result;
}
+#endif
__attribute__((hot))
static inline uint8_t memory_read_dummy(struct nes_state *state, uint32_t offset) {
state->cpu.cycles++;
ppu_tick(state);
- // apu_tick(state);
+ apu_tick(state);
if(offset >= 0x2000 && offset < 0x4000) {
return ppu_read(state, offset);
@@ -46,7 +83,7 @@ __attribute__((hot))
static inline void memory_write(struct nes_state *state, uint32_t offset, uint8_t value) {
state->cpu.cycles++;
ppu_tick(state);
- // apu_tick(state);
+ apu_tick(state);
if(offset < 0x2000) {
state->ram[offset & 0x07ff] = value;
@@ -55,32 +92,23 @@ static inline void memory_write(struct nes_state *state, uint32_t offset, uint8_
ppu_write(state, offset, value);
} else if(offset < 0x4018) {
- // APU + joypad + DMA
if(offset == 0x4014) {
ppu_dma_4014(state, value);
- // } else if(offset == 0x4015) { // DMC Enable (APU)
- // state->apu.dmc_dma_enabled = (value & 0x10) ? 1 : 0;
-
} else if(offset == 0x4016) {
+ // joypad strobe
uint8_t prev = state->ppu.input_strobe;
state->ppu.input_strobe = value & 1;
if(prev == 1 && (value & 1) == 0) {
- // Latch current inputs
state->ppu.input_latch[0] = state->ppu.input[0];
state->ppu.input_latch[1] = state->ppu.input[1];
state->ppu.input_bit[0] = 0;
state->ppu.input_bit[1] = 0;
}
- // } else if(offset == 0x4017) { // Frame Counter (APU)
- // state->apu.mode = (value >> 7) & 1;
- // state->apu.irq_inhibit = (value >> 6) & 1;
- // state->apu.frame_cycle = 0;
- // if(state->apu.irq_inhibit) {
- // state->apu.irq_pending = 0;
- // }
+ } else if(offset >= 0x4010 && offset <= 0x4017) {
+ apu_write(state, offset, value);
}
} else if(offset >= 0x6000) { // NOTE(peter): Might need to move this upwards when we implement a mapper that has prg_ram_*