Max/SameBoy
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Rewrote MBC support

Browse Source
This commit is contained in:
Lior Halphon 2016-07-09 17:34:55 +03:00
parent 78a809795e
commit c6bafe3fc3
6 changed files with 175 additions and 140 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Core/debugger.c
View File

@ -855,7 +855,7 @@ static bool mbc(GB_gameboy_t *gb, char *arguments)
GB_log(gb, "RAM is curently %s\n", gb->mbc_ram_enable? "enabled" : "disabled");
}
if (cartridge->mbc_type == GB_MBC1) {
GB_log(gb, "MBC1 banking mode is %s\n", gb->mbc_ram_banking? "RAM" : "ROM");
GB_log(gb, "MBC1 banking mode is %s\n", gb->mbc1.mode == 1 ? "RAM" : "ROM");
}
}

57
Core/gb.c
View File

@ -14,50 +14,7 @@
#include "joypad.h"
#include "display.h"
#include "debugger.h"
static const GB_cartridge_t cart_defs[256] = {
// From http://gbdev.gg8.se/wiki/articles/The_Cartridge_Header#0147_-_Cartridge_Type
/* MBC RAM BAT. RTC RUMB. */
{ GB_NO_MBC, false, false, false, false}, // 00h ROM ONLY
{ GB_MBC1 , false, false, false, false}, // 01h MBC1
{ GB_MBC1 , true , false, false, false}, // 02h MBC1+RAM
{ GB_MBC1 , true , true , false, false}, // 03h MBC1+RAM+BATTERY
[5] =
{ GB_MBC2 , true , false, false, false}, // 05h MBC2
{ GB_MBC2 , true , true , false, false}, // 06h MBC2+BATTERY
[8] =
{ GB_NO_MBC, true , false, false, false}, // 08h ROM+RAM
{ GB_NO_MBC, true , true , false, false}, // 09h ROM+RAM+BATTERY
[0xB] =
// Todo: What are these?
{ GB_NO_MBC, false, false, false, false}, // 0Bh MMM01
{ GB_NO_MBC, false, false, false, false}, // 0Ch MMM01+RAM
{ GB_NO_MBC, false, false, false, false}, // 0Dh MMM01+RAM+BATTERY
[0xF] =
{ GB_MBC3 , false, true, true , false}, // 0Fh MBC3+TIMER+BATTERY
{ GB_MBC3 , true , true, true , false}, // 10h MBC3+TIMER+RAM+BATTERY
{ GB_MBC3 , false, false, false, false}, // 11h MBC3
{ GB_MBC3 , true , false, false, false}, // 12h MBC3+RAM
{ GB_MBC3 , true , true , false, false}, // 13h MBC3+RAM+BATTERY
[0x15] =
// Todo: Do these exist?
{ GB_MBC4 , false, false, false, false}, // 15h MBC4
{ GB_MBC4 , true , false, false, false}, // 16h MBC4+RAM
{ GB_MBC4 , true , true , false, false}, // 17h MBC4+RAM+BATTERY
[0x19] =
{ GB_MBC5 , false, false, false, false}, // 19h MBC5
{ GB_MBC5 , true , false, false, false}, // 1Ah MBC5+RAM
{ GB_MBC5 , true , true , false, false}, // 1Bh MBC5+RAM+BATTERY
{ GB_MBC5 , false, false, false, true }, // 1Ch MBC5+RUMBLE
{ GB_MBC5 , true , false, false, true }, // 1Dh MBC5+RUMBLE+RAM
{ GB_MBC5 , true , true , false, true }, // 1Eh MBC5+RUMBLE+RAM+BATTERY
[0xFC] =
// Todo: What are these?
{ GB_NO_MBC, false, false, false, false}, // FCh POCKET CAMERA
{ GB_NO_MBC, false, false, false, false}, // FDh BANDAI TAMA5
{ GB_NO_MBC, false, false, false, false}, // FEh HuC3
{ GB_NO_MBC, true , true , false, false}, // FFh HuC1+RAM+BATTERY
};
#include "mbc.h"
void GB_attributed_logv(GB_gameboy_t *gb, GB_log_attributes attributes, const char *fmt, va_list args)
{
@ -131,7 +88,7 @@ void GB_init(GB_gameboy_t *gb)
gb->sprite_palletes_rgb[5] = gb->sprite_palletes_rgb[1] = gb->background_palletes_rgb[1] = 0xAAAAAAAA;
gb->sprite_palletes_rgb[6] = gb->sprite_palletes_rgb[2] = gb->background_palletes_rgb[2] = 0x55555555;
gb->input_callback = default_input_callback;
gb->cartridge_type = &cart_defs[0]; // Default cartridge type
gb->cartridge_type = &GB_cart_defs[0]; // Default cartridge type
gb->io_registers[GB_IO_JOYP] = 0xF;
}
@ -155,7 +112,7 @@ void GB_init_cgb(GB_gameboy_t *gb)
gb->last_vblank = clock();
gb->cgb_ram_bank = 1;
gb->input_callback = default_input_callback;
gb->cartridge_type = &cart_defs[0]; // Default cartridge type
gb->cartridge_type = &GB_cart_defs[0]; // Default cartridge type
gb->io_registers[GB_IO_JOYP] = 0xF;
}
@ -197,12 +154,18 @@ int GB_load_rom(GB_gameboy_t *gb, const char *path)
if (!f) return errno;
fseek(f, 0, SEEK_END);
gb->rom_size = (ftell(f) + 0x3FFF) & ~0x3FFF; /* Round to bank */
/* And then round to a power of two */
while (gb->rom_size & (gb->rom_size - 1)) {
/* I promise this works. */
gb->rom_size |= gb->rom_size >> 1;
gb->rom_size++;
}
fseek(f, 0, SEEK_SET);
gb->rom = malloc(gb->rom_size);
memset(gb->rom, 0xFF, gb->rom_size); /* Pad with 0xFFs */
fread(gb->rom, gb->rom_size, 1, f);
fclose(f);
gb->cartridge_type = &cart_defs[gb->rom[0x147]];
gb->cartridge_type = &GB_cart_defs[gb->rom[0x147]];
if (gb->cartridge_type->has_ram) {
static const int ram_sizes[256] = {0, 0x800, 0x2000, 0x8000, 0x20000, 0x10000};
gb->mbc_ram_size = ram_sizes[gb->rom[0x149]];

25
Core/gb.h
View File

@ -226,7 +226,30 @@ typedef struct GB_gameboy_s {
uint8_t mbc_ram_bank;
uint32_t mbc_ram_size;
bool mbc_ram_enable;
bool mbc_ram_banking;
union {
struct {
uint8_t bank_low:5;
uint8_t bank_high:3;
uint8_t mode:1;
} mbc1;
struct {
uint8_t rom_bank:4;
} mbc2;
struct {
uint8_t rom_bank:7;
uint8_t padding:1;
uint8_t ram_bank:4;
} mbc3;
struct {
uint8_t rom_bank_low;
uint8_t rom_bank_high:1;
uint8_t ram_bank:4;
} mbc5;
};
uint16_t mbc_rom0_bank; /* For some MBC1 wirings. */
);

78
Core/mbc.c Normal file
View File

@ -0,0 +1,78 @@
#include <stdbool.h>
#include "gb.h"
const GB_cartridge_t GB_cart_defs[256] = {
// From http://gbdev.gg8.se/wiki/articles/The_Cartridge_Header#0147_-_Cartridge_Type
/* MBC RAM BAT. RTC RUMB. */
{ GB_NO_MBC, false, false, false, false}, // 00h ROM ONLY
{ GB_MBC1 , false, false, false, false}, // 01h MBC1
{ GB_MBC1 , true , false, false, false}, // 02h MBC1+RAM
{ GB_MBC1 , true , true , false, false}, // 03h MBC1+RAM+BATTERY
[5] =
{ GB_MBC2 , true , false, false, false}, // 05h MBC2
{ GB_MBC2 , true , true , false, false}, // 06h MBC2+BATTERY
[8] =
{ GB_NO_MBC, true , false, false, false}, // 08h ROM+RAM
{ GB_NO_MBC, true , true , false, false}, // 09h ROM+RAM+BATTERY
[0xB] =
// Todo: What are these?
{ GB_NO_MBC, false, false, false, false}, // 0Bh MMM01
{ GB_NO_MBC, false, false, false, false}, // 0Ch MMM01+RAM
{ GB_NO_MBC, false, false, false, false}, // 0Dh MMM01+RAM+BATTERY
[0xF] =
{ GB_MBC3 , false, true, true , false}, // 0Fh MBC3+TIMER+BATTERY
{ GB_MBC3 , true , true, true , false}, // 10h MBC3+TIMER+RAM+BATTERY
{ GB_MBC3 , false, false, false, false}, // 11h MBC3
{ GB_MBC3 , true , false, false, false}, // 12h MBC3+RAM
{ GB_MBC3 , true , true , false, false}, // 13h MBC3+RAM+BATTERY
[0x15] =
// Todo: Do these exist?
{ GB_MBC4 , false, false, false, false}, // 15h MBC4
{ GB_MBC4 , true , false, false, false}, // 16h MBC4+RAM
{ GB_MBC4 , true , true , false, false}, // 17h MBC4+RAM+BATTERY
[0x19] =
{ GB_MBC5 , false, false, false, false}, // 19h MBC5
{ GB_MBC5 , true , false, false, false}, // 1Ah MBC5+RAM
{ GB_MBC5 , true , true , false, false}, // 1Bh MBC5+RAM+BATTERY
{ GB_MBC5 , false, false, false, true }, // 1Ch MBC5+RUMBLE
{ GB_MBC5 , true , false, false, true }, // 1Dh MBC5+RUMBLE+RAM
{ GB_MBC5 , true , true , false, true }, // 1Eh MBC5+RUMBLE+RAM+BATTERY
[0xFC] =
// Todo: What are these?
{ GB_NO_MBC, false, false, false, false}, // FCh POCKET CAMERA
{ GB_NO_MBC, false, false, false, false}, // FDh BANDAI TAMA5
{ GB_NO_MBC, false, false, false, false}, // FEh HuC3
{ GB_NO_MBC, true , true , false, false}, // FFh HuC1+RAM+BATTERY
};
void GB_update_mbc_mappings(GB_gameboy_t *gb)
{
switch (gb->cartridge_type->mbc_type) {
case GB_NO_MBC: case GB_MBC4: return;
case GB_MBC1:
/* Standard MBC1 wiring: */
if (gb->mbc1.mode == 0) {
gb->mbc_rom_bank = gb->mbc1.bank_low | (gb->mbc1.bank_high << 5);
gb->mbc_ram_bank = 0;
}
else {
gb->mbc_rom_bank = gb->mbc1.bank_low;
gb->mbc_ram_bank = gb->mbc1.bank_high;
}
break;
case GB_MBC2:
gb->mbc_rom_bank = gb->mbc2.rom_bank;
break;
case GB_MBC3:
gb->mbc_rom_bank = gb->mbc3.rom_bank;
gb->mbc_ram_bank = gb->mbc3.ram_bank;
break;
case GB_MBC5:
gb->mbc_rom_bank = gb->mbc5.rom_bank_low | (gb->mbc5.rom_bank_high << 8);
gb->mbc_ram_bank = gb->mbc5.ram_bank;
break;
}
if (gb->mbc_rom_bank == 0 && gb->cartridge_type->mbc_type != GB_MBC5) {
gb->mbc_rom_bank = 1;
}
}

8
Core/mbc.h Normal file
View File

@ -0,0 +1,8 @@
#ifndef MBC_h
#define MBC_h
#include "gb.h"
extern const GB_cartridge_t GB_cart_defs[256];
void GB_update_mbc_mappings(GB_gameboy_t *gb);
#endif /* MBC_h */

145
Core/memory.c
View File

@ -5,6 +5,7 @@
#include "display.h"
#include "memory.h"
#include "debugger.h"
#include "mbc.h"
typedef uint8_t GB_read_function_t(GB_gameboy_t *gb, uint16_t addr);
typedef void GB_write_function_t(GB_gameboy_t *gb, uint16_t addr, uint8_t value);
@ -22,15 +23,14 @@ static uint8_t read_rom(GB_gameboy_t *gb, uint16_t addr)
if (!gb->rom_size) {
return 0xFF;
}
return gb->rom[addr];
unsigned int effective_address = (addr & 0x3FFF) + gb->mbc_rom0_bank * 0x4000;
return gb->rom[effective_address & (gb->rom_size - 1)];
}
static uint8_t read_mbc_rom(GB_gameboy_t *gb, uint16_t addr)
{
if (gb->mbc_rom_bank >= gb->rom_size / 0x4000) {
return 0xFF;
}
return gb->rom[(addr & 0x3FFF) + gb->mbc_rom_bank * 0x4000];
unsigned int effective_address = (addr & 0x3FFF) + gb->mbc_rom_bank * 0x4000;
return gb->rom[effective_address & (gb->rom_size - 1)];
}
static uint8_t read_vram(GB_gameboy_t *gb, uint16_t addr)
@ -43,22 +43,19 @@ static uint8_t read_vram(GB_gameboy_t *gb, uint16_t addr)
static uint8_t read_mbc_ram(GB_gameboy_t *gb, uint16_t addr)
{
if (!gb->mbc_ram_enable) return 0xFF;
if (gb->cartridge_type->has_rtc && gb->mbc_ram_bank >= 8 && gb->mbc_ram_bank <= 0xC) {
/* RTC read */
gb->rtc_high |= ~0xC1; /* Not all bytes in RTC high are used. */
return gb->rtc_data[gb->mbc_ram_bank - 8];
}
unsigned int ram_index = (addr & 0x1FFF) + gb->mbc_ram_bank * 0x2000;
if (!gb->mbc_ram_enable)
{
GB_log(gb, "Read from %02x:%04x (%06x) (Disabled MBC RAM)\n", gb->mbc_ram_bank, addr, ram_index);
if (!gb->mbc_ram) {
return 0xFF;
}
if (ram_index >= gb->mbc_ram_size) {
GB_log(gb, "Read from %02x:%04x (%06x) (Unmapped MBC RAM)\n", gb->mbc_ram_bank, addr, ram_index);
return 0xFF;
}
return gb->mbc_ram[(addr & 0x1FFF) + gb->mbc_ram_bank * 0x2000];
return gb->mbc_ram[((addr & 0x1FFF) + gb->mbc_ram_bank * 0x2000) & (gb->mbc_ram_size - 1)];
}
static uint8_t read_ram(GB_gameboy_t *gb, uint16_t addr)
@ -205,75 +202,41 @@ uint8_t GB_read_memory(GB_gameboy_t *gb, uint16_t addr)
static void write_mbc(GB_gameboy_t *gb, uint16_t addr, uint8_t value)
{
if (gb->cartridge_type->mbc_type == GB_NO_MBC) return;
switch (addr >> 12) {
case 0:
case 1:
gb->mbc_ram_enable = value == 0x0a;
break;
case 2:
bank_low:
/* Bank number, lower bits */
if (gb->cartridge_type->mbc_type == GB_MBC1) {
value &= 0x1F;
}
if (gb->cartridge_type->mbc_type != GB_MBC5 && !value) {
value++;
}
gb->mbc_rom_bank = (gb->mbc_rom_bank & 0x100) | value;
break;
case 3:
if (gb->cartridge_type->mbc_type != GB_MBC5) goto bank_low;
if (value > 1) {
GB_log(gb, "Bank overflow: [%x] <- %d\n", addr, value);
}
gb->mbc_rom_bank = (gb->mbc_rom_bank & 0xFF) | value << 8;
break;
case 4:
case 5:
if (gb->cartridge_type->mbc_type == GB_MBC1) {
if (gb->mbc_ram_banking) {
gb->mbc_ram_bank = value & 0x3;
}
else {
gb->mbc_rom_bank = (gb->mbc_rom_bank & 0x1F) | ((value & 0x3) << 5);
}
}
else {
gb->mbc_ram_bank = value;
/* Some games assume banks wrap around. We can do this if RAM size is a power of two */
if (gb->mbc_ram_bank >= gb->mbc_ram_size / 0x2000 && (gb->mbc_ram_size & (gb->mbc_ram_size - 1)) == 0 && gb->mbc_ram_size != 0) {
gb->mbc_ram_bank %= gb->mbc_ram_size / 0x2000;
}
switch (gb->cartridge_type->mbc_type) {
case GB_NO_MBC: case GB_MBC4: return;
case GB_MBC1:
switch (addr & 0xF000) {
case 0x0000: case 0x1000: gb->mbc_ram_enable = (value & 0xF) == 0xA; break;
case 0x2000: case 0x3000: gb->mbc1.bank_low = value; break;
case 0x4000: case 0x5000: gb->mbc1.bank_high = value; break;
case 0x6000: case 0x7000: gb->mbc1.mode = value; break;
}
break;
case 6:
case 7:
if (gb->cartridge_type->mbc_type == GB_MBC1) {
value &= 1;
if (value & !gb->mbc_ram_banking) {
gb->mbc_ram_bank = gb->mbc_rom_bank >> 5;
gb->mbc_rom_bank &= 0x1F;
}
else if (value & !gb->mbc_ram_banking) {
gb->mbc_rom_bank = gb->mbc_rom_bank | (gb->mbc_ram_bank << 5);
gb->mbc_ram_bank = 0;
}
gb->mbc_ram_banking = value;
case GB_MBC2:
switch (addr & 0xF000) {
/* Todo: is this correct? */
case 0x0000: case 0x1000: if (!(addr & 0x100)) gb->mbc_ram_enable = value & 0x1; break;
case 0x2000: case 0x3000: if ( addr & 0x100) gb->mbc2.rom_bank = value; break;
}
break;
case GB_MBC3:
switch (addr & 0xF000) {
case 0x0000: case 0x1000: gb->mbc_ram_enable = (value & 0xF) == 0xA; break;
case 0x2000: case 0x3000: gb->mbc3.rom_bank = value; break;
case 0x4000: case 0x5000: gb->mbc3.ram_bank = value; break;
case 0x6000: case 0x7000: /* Todo: Clock latching support */ break;
}
break;
case GB_MBC5:
switch (addr & 0xF000) {
case 0x0000: case 0x1000: gb->mbc_ram_enable = (value & 0xF) == 0xA; break;
case 0x2000: gb->mbc5.rom_bank_low = value; break;
case 0x3000: gb->mbc5.rom_bank_high = value; break;
case 0x4000: case 0x5000: gb->mbc5.ram_bank = value; break;
}
break;
}
/* Some games assume banks wrap around. We can do this if ROM size is a power of two */
if (gb->mbc_rom_bank >= gb->rom_size / 0x4000 && (gb->rom_size & (gb->rom_size - 1)) == 0 && gb->rom_size != 0) {
gb->mbc_rom_bank %= gb->rom_size / 0x4000;
}
if (gb->cartridge_type->mbc_type != GB_MBC5 && !gb->mbc_rom_bank) {
gb->mbc_rom_bank = 1;
}
GB_update_mbc_mappings(gb);
}
static void write_vram(GB_gameboy_t *gb, uint16_t addr, uint8_t value)
@ -287,23 +250,23 @@ static void write_vram(GB_gameboy_t *gb, uint16_t addr, uint8_t value)
static void write_mbc_ram(GB_gameboy_t *gb, uint16_t addr, uint8_t value)
{
if (gb->mbc_ram_bank >= 8 && gb->mbc_ram_bank <= 0xC) {
/* RTC write*/
if (!gb->mbc_ram_enable) return;
if (gb->cartridge_type->has_rtc && gb->mbc_ram_bank >= 8 && gb->mbc_ram_bank <= 0xC) {
/* RTC read */
gb->rtc_data[gb->mbc_ram_bank - 8] = value;
gb->rtc_high |= ~0xC1; /* Not all bytes in RTC high are used. */
}
if (gb->cartridge_type->mbc_type == GB_MBC2) {
value &= 0xF;
}
if (!gb->mbc_ram) {
return;
}
unsigned int ram_index = (addr & 0x1FFF) + gb->mbc_ram_bank * 0x2000;
if (!gb->mbc_ram_enable)
{
GB_log(gb, "Write to %02x:%04x (%06x) (Disabled MBC RAM)\n", gb->mbc_ram_bank, addr, ram_index);
return;
}
if (ram_index >= gb->mbc_ram_size) {
GB_log(gb, "Write to %02x:%04x (%06x) (Unmapped MBC RAM)\n", gb->mbc_ram_bank, addr, ram_index);
return;
}
gb->mbc_ram[(addr & 0x1FFF) + gb->mbc_ram_bank * 0x2000] = value;
gb->mbc_ram[((addr & 0x1FFF) + gb->mbc_ram_bank * 0x2000) & (gb->mbc_ram_size - 1)] = value;
}
static void write_ram(GB_gameboy_t *gb, uint16_t addr, uint8_t value)