*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "mapinc.h"
+//16 bits of ram in total
+//only use bottom 4 bits as ram though
+static uint8 mapper228_ram[4];
+
+static SFORMAT StateRegs[]=
+{
+ { mapper228_ram, 4, "MAPPER_RAM" },
+ { 0 }
+};
+
+static DECLFR(Mapper228_read)
+{
+ return mapper228_ram[A & 3] & 0xF;
+}
+
static DECLFW(Mapper228_write)
{
- uint32 page,pagel,pageh;
+ uint32 page, pagel, pageh;
- MIRROR_SET((A>>13)&1);
+ //write to ram
+ if (A < 0x6000)
+ {
+ mapper228_ram[A & 3] = V;
+ return;
+ }
+ MIRROR_SET((A >> 13) & 1);
+ page = (A >> 7) & 0x3F;
- page=(A>>7)&0x3F;
- //printf("%04x\n",A);
- if((page&0x30)==0x30)
- page-=0x10;
-
- pagel=pageh=(page<<1) + (((A>>6)&1)&((A>>5)&1));
- pageh+=((A>>5)&1)^1;
+ if( (page & 0x30) == 0x30)
+ page -= 0x10;
- ROM_BANK16(0x8000,pagel);
- ROM_BANK16(0xC000,pageh);
- VROM_BANK8( (V&0x3) | ((A&0xF)<<2) );
+ pagel = pageh = (page << 1) + (((A >> 6) & 1) & ((A >> 5) & 1));
+ pageh += ((A >> 5) & 1) ^ 1;
+
+ ROM_BANK16(0x8000,pagel);
+ ROM_BANK16(0xC000,pageh);
+ VROM_BANK8( (V&0x3) | ((A&0xF)<<2) );
}
static void A52Reset(void)
{
- Mapper228_write(0,0);
+ Mapper228_write(0x8000, 0);
}
void Mapper228_init(void)
{
- MapperReset=A52Reset;
- A52Reset();
- SetWriteHandler(0x8000,0xffff,Mapper228_write);
+ MapperReset=A52Reset;
+ A52Reset();
+ SetWriteHandler(0x8000, 0xFFFF, Mapper228_write);
+ SetWriteHandler(0x4020, 0x5FFF, Mapper228_write);
+ SetReadHandler (0x4020, 0x5FFF, Mapper228_read);
+ AddExState(StateRegs, ~0, 0, 0);
}