Files
ci-libretro-fceumm/src/boards/428.c
NewRisingSun 9cfea5b7d1 Typos in 428.c
2021-04-14 19:29:08 +02:00

106 lines
2.2 KiB
C

/* FCE Ultra - NES/Famicom Emulator
*
* Copyright notice for this file:
*
* Copyright (C) 2008 -2020 dragon2snow,loong2snow from www.nesbbs.com
*
* 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
*
*
*/
#include "mapinc.h"
static uint8 regs[4];
static uint8 hrd_flag;
static SFORMAT StateRegs[] =
{
{ &hrd_flag, 1, "FLAG" },
{ regs, 4, "REGS" },
{ 0 }
};
static void Sync(void) {
int mask = regs[2] >> 6; /* There is an CNROM mode that takes either two or four inner CHR banks from a CNROM-like latch register at $8000-$FFFF. */
if (regs[1] & 0x10)
setprg32(0x8000,(regs[1] & 0xC0) >> 6);
else
{
setprg16(0x8000, (regs[1] & 0xE0) >> 5);
setprg16(0xC000, (regs[1] & 0xE0) >> 5);
}
setchr8(((regs[1] & 0x07) & ~mask) | regs[0] & mask);
setmirror((regs[1] & 0x8) ? 0 : 1);
}
static DECLFW(WriteHi) {
regs[0] = V;
Sync();
}
static DECLFW(WriteLo) {
regs[A & 0x03] = V;
Sync();
}
static DECLFR(ReadLo) {
return hrd_flag;
}
static void Power(void) {
hrd_flag = 0; /* Solder pad, selecting different menus */
regs[0] = 0;
regs[1] = 0;
regs[2] = 0;
Sync();
SetWriteHandler(0x8000, 0xFFFF, WriteHi);
SetWriteHandler(0x6001, 0x6002, WriteLo);
SetReadHandler(0x6000, 0x7FFF, ReadLo);
SetReadHandler(0x8000, 0xFFFF, CartBR);
}
static void StateRestore(int version) {
Sync();
}
static void Reset(void) {
hrd_flag++;
hrd_flag &= 3;
regs[0] = 0;
regs[1] = 0;
regs[2] = 0;
Sync();
}
void Mapper428_Init(CartInfo *info) {
hrd_flag = 0;
Sync();
info->Power = Power;
info->Reset = Reset;
AddExState(&StateRegs, ~0, 0, 0);
GameStateRestore = StateRestore;
}