#include "mapinc.h"
+//16 bits of ram in total
+//only use bottom 4 bits as ram though
+static uint8 mapper228_ram[4];
+
+static DECLFR(Mapper228_read)
+{
+ return mapper228_ram[A & 3] & 0xF;
+}
+
static DECLFW(Mapper228_write)
{
uint32 page,pagel,pageh;
+ //write to ram
+ if (A < 0x6000)
+ {
+ mapper228_ram[A & 3] = V;
+ return;
+ }
MIRROR_SET((A>>13)&1);
-
page=(A>>7)&0x3F;
- //printf("%04x\n",A);
+
if((page&0x30)==0x30)
page-=0x10;
static void A52Reset(void)
{
- Mapper228_write(0,0);
+ Mapper228_write(0x8000, 0);
}
void Mapper228_init(void)
{
MapperReset=A52Reset;
A52Reset();
- SetWriteHandler(0x8000,0xffff,Mapper228_write);
+ SetWriteHandler(0x8000, 0xFFFF, Mapper228_write);
+ SetWriteHandler(0x4020, 0x5FFF, Mapper228_write);
+ SetReadHandler (0x4020, 0x5FFF, Mapper228_read);
+ AddExState(mapper228_ram, 4, 0, "MRAM");
}