Files
ci-libretro-fceumm/src/boards/401.c
negativeExponent c42a1d8a8e Update
2022-02-20 06:46:45 +08:00

97 lines
2.6 KiB
C

/* FCEUmm - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2020
*
* 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 401 (reference from NewRisingSun)
* Super 19-in-1 (VIP19) (crc 0x2F497313)
*
*/
#include "mapinc.h"
#include "mmc3.h"
static uint8 dipswitch = 0;
static void M401CW(uint32 A, uint8 V) {
uint32 mask = (0xFF >> (~EXPREGS[2] & 0xF));
uint32 bank = (EXPREGS[0] | ((EXPREGS[2] << 4) & 0xF00));
setchr1(A, (V & mask) | bank);
}
static void M401PW(uint32 A, uint8 V) {
if ((dipswitch & 1) && (EXPREGS[1] & 0x80)) {
/* openbus */
} else {
uint32 mask = (~EXPREGS[3] & 0x1F);
uint32 bank = (EXPREGS[1] & 0x1F) | (EXPREGS[2] & 0x80) |
((dipswitch & 2) ? (EXPREGS[2] & 0x20) : ((EXPREGS[1] >> 1) & 0x20)) |
((dipswitch & 4) ? (EXPREGS[2] & 0x40) : ((EXPREGS[1] << 1) & 0x40));
setprg8(A, (V & mask) | bank);
}
}
static DECLFR(M401Read) {
if ((dipswitch & 1) && (EXPREGS[1] & 0x80))
return X.DB;
return CartBR(A);
}
static DECLFW(M401Write) {
/* FCEU_printf("Wr A:%04x V:%02x index:%d\n", A, V, EXPREGS[4]); */
if (!(EXPREGS[3] & 0x40)) {
EXPREGS[EXPREGS[4]] = V;
EXPREGS[4] = (EXPREGS[4] + 1) & 3;
FixMMC3PRG(MMC3_cmd);
FixMMC3CHR(MMC3_cmd);
}
CartBW(A, V);
}
static void M401Reset(void) {
dipswitch = (dipswitch + 1) & 7;
FCEU_printf("dipswitch = %d\n", dipswitch);
EXPREGS[0] = 0x00;
EXPREGS[1] = 0x00;
EXPREGS[2] = 0x0F;
EXPREGS[3] = 0x00;
EXPREGS[4] = 0x00;
MMC3RegReset();
}
static void M401Power(void) {
dipswitch = 7;
EXPREGS[0] = 0x00;
EXPREGS[1] = 0x00;
EXPREGS[2] = 0x0F;
EXPREGS[3] = 0x00;
EXPREGS[4] = 0x00;
GenMMC3Power();
SetReadHandler(0x8000, 0xFFFF, M401Read);
SetWriteHandler(0x6000, 0x7FFF, M401Write);
}
void Mapper401_Init(CartInfo *info) {
GenMMC3_Init(info, 256, 256, 8, 0);
cwrap = M401CW;
pwrap = M401PW;
info->Power = M401Power;
info->Reset = M401Reset;
AddExState(EXPREGS, 5, 0, "EXPR");
AddExState(&dipswitch, 1, 0, "DPSW");
}