Files
ci-libretro-fceumm/src/boards/468_mmc3.h
2023-01-03 01:01:38 +01:00

81 lines
3.1 KiB
C

#define MMC3_reg regByte
#define MMC3_index regByte[8]
#define MMC3_mirroring regByte[9]
#define MMC3_wram regByte[10]
#define MMC3_reload regByte[11]
#define MMC3_count regByte[12]
#define MMC3_irq regByte[13]
#define MMC3_lastReg regByte[14]
static void MMC3_sync () {
int chrAND =mapper &0x01? 0xFF: 0x7F;
int OR =prgOR | (misc2 &1? 12: 0);
setprg8(0x8000 ^(MMC3_index <<8 &0x4000), MMC3_reg[6] &prgAND | OR &~prgAND);
setprg8(0xA000, MMC3_reg[7] &prgAND | OR &~prgAND);
setprg8(0xC000 ^(MMC3_index <<8 &0x4000), 0xFE &prgAND | OR &~prgAND);
setprg8(0xE000, 0xFF &prgAND | OR &~prgAND);
setchr1(0x0000 ^(MMC3_index <<5 &0x1000),(MMC3_reg[0] &0xFE)&chrAND);
setchr1(0x0400 ^(MMC3_index <<5 &0x1000),(MMC3_reg[0] |0x01)&chrAND);
setchr1(0x0800 ^(MMC3_index <<5 &0x1000),(MMC3_reg[1] &0xFE)&chrAND);
setchr1(0x0C00 ^(MMC3_index <<5 &0x1000),(MMC3_reg[1] |0x01)&chrAND);
setchr1(0x1000 ^(MMC3_index <<5 &0x1000), MMC3_reg[2] &chrAND);
setchr1(0x1400 ^(MMC3_index <<5 &0x1000), MMC3_reg[3] &chrAND);
setchr1(0x1800 ^(MMC3_index <<5 &0x1000), MMC3_reg[4] &chrAND);
setchr1(0x1C00 ^(MMC3_index <<5 &0x1000), MMC3_reg[5] &chrAND);
if (mapper &2) switch(MMC3_mirroring &3) {
case 0: setmirror(MI_V); break;
case 1: setmirror(MI_H); break;
case 2: setmirror(MMC3_reg[MMC3_lastReg] &0x80? MI_1: MI_0); break;
case 3: setmirror(MI_1); break;
} else
setmirror(MMC3_mirroring &1? MI_H: MI_V);
}
static DECLFW(MMC3_writeReg) {
switch(A &0xE001) {
case 0x8000: MMC3_index =V; sync(); break;
case 0x8001: MMC3_reg[MMC3_index &7] =V; sync(); break;
case 0xA000: MMC3_mirroring =V; sync(); break;
case 0xA001: MMC3_wram =V; sync(); break;
case 0xC000: MMC3_reload =V; break;
case 0xC001: MMC3_count =0; break;
case 0xE000: MMC3_irq =0; X6502_IRQEnd(FCEU_IQEXT); break;
case 0xE001: MMC3_irq =1; break;
}
}
static void MMC3_horizontalBlanking(void) {
MMC3_count =!MMC3_count? MMC3_reload: --MMC3_count;
if (!MMC3_count && MMC3_irq) X6502_IRQBegin(FCEU_IQEXT);
}
static void FP_FASTAPASS(1) MMC3_ppuHook(uint32 A) {
A &=0x1FFF;
if (MMC3_index &0x80) A ^=0x1000;
if (A <0x1000)
MMC3_lastReg =A >>11;
else
MMC3_lastReg =(A >>10) -2;
if ((MMC3_mirroring &3) ==2) setmirror(MMC3_reg[MMC3_lastReg] &0x80? MI_1: MI_0);
}
void MMC3_reset(uint8 clearRegs) {
sync =MMC3_sync;
GameHBIRQHook =MMC3_horizontalBlanking;
if (mapper &2) PPU_hook =MMC3_ppuHook;
prgAND =mapperFlags &8? (mapperFlags &4? (mapperFlags &2? (misc2 &2? 0x07: 0x0F): 0x1F): 0x3F): 0x7F;
SetWriteHandler(0x8000, 0xFFFF, MMC3_writeReg);
MMC3_mirroring =1; /* "Legendary Games of NES' 509-in-1"'s menu runs as MMC3 with H mirroring and expects that setting to stay when running a mapper 206 game such as Legend of Valkyrie. */
sync();
}
#undef MMC3_reg
#undef MMC3_index
#undef MMC3_mirroring
#undef MMC3_wram
#undef MMC3_reload
#undef MMC3_count
#undef MMC3_irq
#undef MMC3_lastReg