Files
ci-libretro-fceumm/src/boards/269.c
2020-10-26 07:41:48 +08:00

100 lines
2.6 KiB
C

/* FCEUmm - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2020 negativeExponent
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
/* NES 2.0 Mapper 269
* Games Xplosion 121-in-1
* 15000-in-1
* 18000-in-1
*/
#include "mapinc.h"
#include "mmc3.h"
static uint8 *CHRROM;
static uint32 CHRROMSIZE;
static void M269CW(uint32 A, uint8 V) {
uint16 NV = V;
if (EXPREGS[2] & 8)
NV &= (1 << ((EXPREGS[2] & 7) + 1)) - 1;
NV |= EXPREGS[0] | ((EXPREGS[2] & 0xF0) << 4);
setchr1(A, NV);
}
static void M269PW(uint32 A, uint8 V) {
uint16 MV = V & ((EXPREGS[3] & 0x3F) ^ 0x3F);
MV |= EXPREGS[1];
MV |= ((EXPREGS[3] & 0x40) << 2);
setprg8(A, MV);
}
static DECLFW(M269Write5) {
if (!(EXPREGS[3] & 0x80)) {
EXPREGS[EXPREGS[4]] = V;
EXPREGS[4] = (EXPREGS[4] + 1) & 3;
FixMMC3PRG(MMC3_cmd);
FixMMC3CHR(MMC3_cmd);
}
}
static void M269Close(void) {
GenMMC3Close();
if (CHRROM)
FCEU_free(CHRROM);
CHRROM = NULL;
}
static void M269Reset(void) {
EXPREGS[0] = EXPREGS[1] = EXPREGS[3] = EXPREGS[4] = 0;
EXPREGS[2] = 0x0F;
MMC3RegReset();
}
static void M269Power(void) {
EXPREGS[0] = EXPREGS[1] = EXPREGS[3] = EXPREGS[4] = 0;
EXPREGS[2] = 0x0F;
GenMMC3Power();
SetWriteHandler(0x5000, 0x5FFF, M269Write5);
}
static uint8 unscrambleCHR(uint8 data) {
return ((data & 0x01) << 6) | ((data & 0x02) << 3) | ((data & 0x04) << 0) | ((data & 0x08) >> 3) |
((data & 0x10) >> 3) | ((data & 0x20) >> 2) | ((data & 0x40) >> 1) | ((data & 0x80) << 0);
}
void Mapper269_Init(CartInfo *info) {
uint32 i;
GenMMC3_Init(info, 512, 0, 8, 0);
cwrap = M269CW;
pwrap = M269PW;
info->Power = M269Power;
info->Reset = M269Reset;
info->Close = M269Close;
AddExState(EXPREGS, 5, 0, "EXPR");
CHRROMSIZE = PRGsize[0];
CHRROM = (uint8*)FCEU_gmalloc(CHRROMSIZE);
/* unscramble CHR data from PRG */
for (i = 0; i < CHRROMSIZE; i++)
CHRROM[i] = unscrambleCHR(PRGptr[0][i]);
SetupCartCHRMapping(0, CHRROM, CHRROMSIZE, 0);
AddExState(CHRROM, CHRROMSIZE, 0, "_CHR");
}