libretro/libretro-fceumm
1
0
Fork 0
mirror of https://github.com/libretro/libretro-fceumm.git synced 2024-12-29 12:23:18 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Mapper 340: Add support for 1 MiB variant

Browse Source
This commit is contained in:
NewRisingSun 2022-03-21 15:31:21 +01:00
parent 3f20020b96
commit c01250c28d
1 changed files with 11 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
src/boards/bmck3036.c
View File

@ -18,41 +18,31 @@
*
*/
/* NES 2.0 mapper 340 is used for a 35-in-1 multicart.
* Its UNIF board name is BMC-K-3036.
* http://wiki.nesdev.com/w/index.php/NES_2.0_Mapper_340
* TODO: Some games are not working...
*/
#include "mapinc.h"
static uint8 regs[2], mirr, mode;
static uint8 regs[2];
static SFORMAT StateRegs[] =
{
{ regs, 2, "REGS" },
{ &mode, 1, "MODE" },
{ &mirr, 1, "MIRR" },
{ 0 }
};
static void Sync(void) {
if (mode) { /* NROM-128 */
setprg16(0x8000, regs[0]);
setprg16(0xC000, regs[0]);
} else { /* UNROM */
setprg16(0x8000, regs[0] | regs[1]);
setprg16(0xC000, regs[0] | 0x07);
if (regs[0] &0x20) { /* NROM-128 */
setprg16(0x8000, regs[0] >>2 &0x20 | regs[0] &0x1F);
setprg16(0xC000, regs[0] >>2 &0x20 | regs[0] &0x1F);
} else { /* UNROM */
setprg16(0x8000, regs[0] >>2 &0x20 | regs[0] | regs[1] &7);
setprg16(0xC000, regs[0] >>2 &0x20 | regs[0] | 7);
}
setchr8(0);
setmirror(mirr);
setmirror((regs[0] &0x40 || regs[0] &0x20 && regs[0] &0x04)? MI_H: MI_V);
}
static DECLFW(M340Write) {
regs[0] = A & 0x1F;
regs[1] = V & 0x07;
mode = A & 0x20;
mirr = ((A & 0x25) == 0x25) ? 0 : 1;
regs[0] = A & 0xFF;
regs[1] = V;
Sync();
}
@ -63,7 +53,7 @@ static void BMCK3036Power(void) {
}
static void BMCK3036Reset(void) {
regs[0] = regs[1] = mode = mirr = 0;
regs[0] = regs[1] = 0;
Sync();
}