Rearrangement and refactoring and optimizations and more accuracy

1 files changed, 95 insertions, 40 deletions

diff --git a/mappers/mapper_001_0.c b/mappers/mapper_001_0.c
index 51d22a2..a449fe7 100644
--- a/mappers/mapper_001_0.c
+++ b/mappers/mapper_001_0.c
@@ -1,7 +1,6 @@
-
-__attribute__((section(".mapper_001_0")))
 static uint8_t mapper_001_0_prg_rom_read(struct nes_state *state, uint32_t addr) {
 	struct mapper_001_0 *mapper = &state->mapper_data.m001_0;
+
 	if(addr >= 0x8000) {
 		if(addr < 0xc000) {
 			return mapper->prg_rom_0[addr & 0x3fff];
@@ -12,10 +11,14 @@ static uint8_t mapper_001_0_prg_rom_read(struct nes_state *state, uint32_t addr)
 	return 0;
 }
 
-__attribute__((section(".mapper_001_0")))
 static void mapper_001_0_prg_rom_write(struct nes_state *state, uint32_t addr, uint8_t value) {
 	struct mapper_001_0 *mapper = &state->mapper_data.m001_0;
-	if(addr < 0x8000) return;
+
+printf("MMC1 write: addr=%04x val=%02x\n", addr, value);
+
+	if(addr < 0x8000) {
+		return;
+	}
 
 	if(value & 0x80) {
 		mapper->shift = 0;
@@ -28,94 +31,146 @@ static void mapper_001_0_prg_rom_write(struct nes_state *state, uint32_t addr, u
 	mapper->shift_count++;
 
 	if(mapper->shift_count == 5) {
-		uint32_t bank;
-		uint8_t reg = (addr >> 13) & 0x03;
+		uint8_t reg = (addr >> 13) & 3;
+
 		switch(reg) {
-			case 0: {// Control
+			case 0: {
 				mapper->control = mapper->shift;
+				switch(mapper->control & 3) {
+					case 0: {
+						state->ines.mirroring = MIRROR_ONESCREEN_LOW;
+					} break;
+
+					case 1: {
+						state->ines.mirroring = MIRROR_ONESCREEN_HIGH;
+					} break;
+
+					case 2: {
+						state->ines.mirroring = MIRROR_VERTICAL;
+					} break;
+
+					case 3: {
+						state->ines.mirroring = MIRROR_HORIZONTAL;
+					} break;
+				}
 			} break;
 
-			case 1: { // CHR bank 0
+			case 1: {
 				mapper->chr_bank0 = mapper->shift;
 				mapper->chr_bank_0 = state->chr_rom + (mapper->chr_bank0 * 0x1000);
 			} break;
 
-			case 2: { // CHR bank 1
+			case 2: {
 				mapper->chr_bank1 = mapper->shift;
 				mapper->chr_bank_1 = state->chr_rom + (mapper->chr_bank1 * 0x1000);
 			} break;
 
-			case 3: { // PRG bank
+			case 3: {
 				mapper->prg_bank = mapper->shift & 0x0f;
+
 				if(mapper->control & 0x08) {
-					// 16KB bank switching
 					if(mapper->control & 0x04) {
-						mapper->prg_rom_0 = state->prg_rom + 0x4000 * 0;
-						mapper->prg_rom_1 = state->prg_rom + 0x4000 * mapper->prg_bank;
+						mapper->prg_rom_0 = state->prg_rom;
+						mapper->prg_rom_1 = state->prg_rom + (mapper->prg_bank * 0x4000);
 					} else {
-						mapper->prg_rom_0 = state->prg_rom + 0x4000 * mapper->prg_bank;
-						mapper->prg_rom_1 = state->prg_rom + 0x4000 * (state->ines.prg_size / 0x4000 - 1);
+						mapper->prg_rom_0 = state->prg_rom + (mapper->prg_bank * 0x4000);
+						mapper->prg_rom_1 = state->prg_rom + (state->ines.prg_size - 0x4000);
 					}
 				} else {
-					// 32KB mode
-					bank = (mapper->prg_bank & 0x0e) * 0x4000;
-					mapper->prg_rom_0 = state->prg_rom + bank;
-					mapper->prg_rom_1 = state->prg_rom + bank + 0x4000;
+					uint32_t base = (mapper->prg_bank & 0x0e) * 0x4000;
+					mapper->prg_rom_0 = state->prg_rom + base;
+					mapper->prg_rom_1 = state->prg_rom + base + 0x4000;
 				}
 			} break;
 		}
+
 		mapper->shift = 0;
 		mapper->shift_count = 0;
 	}
 }
 
-__attribute__((section(".mapper_001_0")))
 static uint8_t mapper_001_0_chr_read(struct nes_state *state, uint32_t addr) {
 	struct mapper_001_0 *mapper = &state->mapper_data.m001_0;
+
 	if(mapper->control & 0x10) {
-		// 4KB mode
 		if(addr < 0x1000) {
-			return mapper->chr_bank_0[addr];
+			return mapper->chr_bank_0[addr & 0xfff];
 		} else {
-			return mapper->chr_bank_1[addr - 0x1000];
+			return mapper->chr_bank_1[addr & 0xfff];
 		}
 	} else {
-		// 8KB mode
-		return mapper->chr_bank_0[addr];
+		return mapper->chr_bank_0[addr & 0x1fff];
 	}
 }
 
-__attribute__((section(".mapper_001_0")))
 static void mapper_001_0_chr_write(struct nes_state *state, uint32_t addr, uint8_t value) {
-	// CHR RAM write (if present)
 	state->chr_ram[addr] = value;
 }
 
-__attribute__((section(".mapper_001_0")))
 static uint8_t mapper_001_0_ciram_read(struct nes_state *state, uint32_t addr) {
-	return state->ciram[addr & 0x3ff];
+	// MMC1 can set mirroring mode dynamically via control register
+	switch(state->ines.mirroring) {
+		case MIRROR_ONESCREEN_LOW:
+			addr = addr & 0x3ff;
+			break;
+		case MIRROR_ONESCREEN_HIGH:
+			addr = 0x400 | (addr & 0x3ff);
+			break;
+		case MIRROR_HORIZONTAL: // Horizontal: NT0↔NT1, NT2↔NT3
+			addr = ((addr >> 1) & 0x400) | (addr & 0x3ff);
+			break;
+		case MIRROR_VERTICAL: // Vertical: NT0↔NT2, NT1↔NT3
+			addr = addr & 0x7ff;
+			break;
+	}
+	return state->ciram[addr];
 }
 
-__attribute__((section(".mapper_001_0")))
 static void mapper_001_0_ciram_write(struct nes_state *state, uint32_t addr, uint8_t value) {
-	state->ciram[addr & 0x3ff] = value;
+	// MMC1 can set mirroring mode dynamically via control register
+	switch(state->ines.mirroring) {
+		case MIRROR_ONESCREEN_LOW:
+			addr = addr & 0x3ff;
+			break;
+		case MIRROR_ONESCREEN_HIGH:
+			addr = 0x400 | (addr & 0x3ff);
+			break;
+		case MIRROR_HORIZONTAL: // Horizontal: NT0↔NT1, NT2↔NT3
+			addr = ((addr >> 1) & 0x400) | (addr & 0x3ff);
+			break;
+		case MIRROR_VERTICAL: // Vertical: NT0↔NT2, NT1↔NT3
+			addr = addr & 0x7ff;
+			break;
+	}
+	state->ciram[addr] = value;
 }
 
-__attribute__((section(".mapper_001_0")))
 static void mapper_001_0_init(struct nes_state *state) {
 	struct mapper_001_0 *mapper = &state->mapper_data.m001_0;
 
+	mapper->shift = 0;
+	mapper->shift_count = 0;
 	mapper->control = 0x0c;
+
+	mapper->prg_bank = 0;
+	mapper->chr_bank0 = 0;
+	mapper->chr_bank1 = 0;
+
 	mapper->prg_rom_0 = state->prg_rom;
 	mapper->prg_rom_1 = state->prg_rom + (state->ines.prg_size - 0x4000);
 
-	mapper->chr_bank_0 = state->chr_rom;
-	mapper->chr_bank_1 = state->chr_rom + 0x1000;
+	if(state->ines.chr_size) {
+		mapper->chr_bank_0 = state->chr_rom;
+		mapper->chr_bank_1 = state->chr_rom + 0x1000;
+	} else {
+		mapper->chr_bank_0 = state->chr_ram;
+		mapper->chr_bank_1 = state->chr_ram + 0x1000;
+	}
 
-	state->mapper_function.prg_rom_read		= mapper_001_0_prg_rom_read;
-	state->mapper_function.prg_rom_write	= mapper_001_0_prg_rom_write;
-	state->mapper_function.chr_read			= mapper_001_0_chr_read;
-	state->mapper_function.chr_write			= mapper_001_0_chr_write;
-	state->mapper_function.ciram_read		= mapper_001_0_ciram_read;
-	state->mapper_function.ciram_write		= mapper_001_0_ciram_write;
+	state->mapper_function.prg_rom_read = mapper_001_0_prg_rom_read;
+	state->mapper_function.prg_rom_write = mapper_001_0_prg_rom_write;
+	state->mapper_function.chr_read = mapper_001_0_chr_read;
+	state->mapper_function.chr_write = mapper_001_0_chr_write;
+	state->mapper_function.ciram_read = mapper_001_0_ciram_read;
+	state->mapper_function.ciram_write = mapper_001_0_ciram_write;
 }