mirror of
https://github.com/dborth/fceugx.git
synced 2024-12-27 09:01:56 +01:00
56 lines
1.3 KiB
C
56 lines
1.3 KiB
C
|
/* Is this an MMC3 workalike piece of hardware, with the addition of
|
||
|
|
a register at $4120 or does it have only partial MMC3 functionality?
|
||
|
|
A good test would be to see if commands 6 and 7 can change PRG banks
|
||
|
|
and of course test the regs >=$c000, on the real cart.
|
||
|
|
*/
|
||
|
|
#include "mapinc.h"
|
||
|
|
|
||
|
|
#define cmd mapbyte1[0]
|
||
|
|
static DECLFW(Mapper189_write)
|
||
|
|
{
|
||
|
|
//if(A>=0xc000) printf("$%04x:$%02x\n",A,V);
|
||
|
|
if((A&0xF100)==0x4100) ROM_BANK32(V>>4);
|
||
|
|
else if((A&0xF100)==0x6100) ROM_BANK32(V&3);
|
||
|
|
else switch(A&0xE001)
|
||
|
|
{
|
||
|
|
case 0xa000:MIRROR_SET(V&1);break;
|
||
|
|
case 0x8000:cmd=V;break;
|
||
|
|
case 0x8001:switch(cmd&7)
|
||
|
|
{
|
||
|
|
case 0:VROM_BANK2(0x0000,V>>1);break;
|
||
|
|
case 1:VROM_BANK2(0x0800,V>>1);break;
|
||
|
|
case 2:VROM_BANK1(0x1000,V);break;
|
||
|
|
case 3:VROM_BANK1(0x1400,V);break;
|
||
|
|
case 4:VROM_BANK1(0x1800,V);break;
|
||
|
|
case 5:VROM_BANK1(0x1C00,V);break;
|
||
|
|
}
|
||
|
|
case 0xc000:IRQLatch=V;break;
|
||
|
|
case 0xc001:IRQCount=IRQLatch;break;
|
||
|
|
case 0xe000:IRQa=0;X6502_IRQEnd(FCEU_IQEXT);break;
|
||
|
|
case 0xe001:IRQa=1;break;
|
||
|
|
break;
|
||
|
|
|
||
|
|
}
|
||
|
|
}
|
||
|
|
void m189irq(void)
|
||
|
|
{
|
||
|
|
if(IRQa)
|
||
|
|
{
|
||
|
|
if(IRQCount)
|
||
|
|
{
|
||
|
|
IRQCount--;
|
||
|
|
if(!IRQCount) X6502_IRQBegin(FCEU_IQEXT);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|
||
|
|
void Mapper189_init(void)
|
||
|
|
{
|
||
|
|
GameHBIRQHook=m189irq;
|
||
|
|
SetWriteHandler(0x4120,0xFFFF,Mapper189_write);
|
||
|
|
SetReadHandler(0x6000,0x7FFF,0);
|
||
|
|
ROM_BANK32(0);
|
||
|
|
}
|
||
|
|
|
||
|
|
|