kopia lustrzana https://github.com/Jean-MarcHarvengt/MCUME
216 wiersze
6.2 KiB
C
Executable File
216 wiersze
6.2 KiB
C
Executable File
/*
|
|
** Nofrendo (c) 1998-2000 Matthew Conte (matt@conte.com)
|
|
**
|
|
**
|
|
** This program is free software; you can redistribute it and/or
|
|
** modify it under the terms of version 2 of the GNU Library General
|
|
** Public License as published by the Free Software Foundation.
|
|
**
|
|
** 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
|
|
** Library General Public License for more details. To obtain a
|
|
** copy of the GNU Library General Public License, write to the Free
|
|
** Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
**
|
|
** Any permitted reproduction of these routines, in whole or in part,
|
|
** must bear this legend.
|
|
**
|
|
**
|
|
** map18.c
|
|
**
|
|
** mapper 18 interface
|
|
** $Id: map018.c,v 1.2 2001/04/27 14:37:11 neil Exp $
|
|
*/
|
|
|
|
#include "noftypes.h"
|
|
#include "nes_mmc.h"
|
|
#include "nes_ppu.h"
|
|
|
|
/* mapper 18: Jaleco SS8806 */
|
|
#define VRC_PBANK(bank, value, high) \
|
|
do { \
|
|
if ((high)) \
|
|
highprgnybbles[(bank)] = (value) & 0x0F; \
|
|
else \
|
|
lowprgnybbles[(bank)] = (value) & 0x0F; \
|
|
mmc_bankrom(8, 0x8000 + ((bank) << 13), (highprgnybbles[(bank)] << 4)+lowprgnybbles[(bank)]); \
|
|
} while (0)
|
|
|
|
#define VRC_VBANK(bank, value, high) \
|
|
{ \
|
|
if ((high)) \
|
|
highnybbles[(bank)] = (value) & 0x0F; \
|
|
else \
|
|
lownybbles[(bank)] = (value) & 0x0F; \
|
|
mmc_bankvrom(1, (bank) << 10, (highnybbles[(bank)] << 4)+lownybbles[(bank)]); \
|
|
}
|
|
|
|
static struct
|
|
{
|
|
int counter, enabled;
|
|
uint8 nybbles[4];
|
|
int clockticks;
|
|
} irq;
|
|
|
|
static void map18_init(void)
|
|
{
|
|
irq.counter = irq.enabled = 0;
|
|
}
|
|
|
|
static uint8 lownybbles[8];
|
|
static uint8 highnybbles[8];
|
|
static uint8 lowprgnybbles[3];
|
|
static uint8 highprgnybbles[3];
|
|
|
|
|
|
static void map18_write(uint32 address, uint8 value)
|
|
{
|
|
switch (address)
|
|
{
|
|
case 0x8000: VRC_PBANK(0, value, 0); break;
|
|
case 0x8001: VRC_PBANK(0, value, 1); break;
|
|
case 0x8002: VRC_PBANK(1, value, 0); break;
|
|
case 0x8003: VRC_PBANK(1, value, 1); break;
|
|
case 0x9000: VRC_PBANK(2, value, 0); break;
|
|
case 0x9001: VRC_PBANK(2, value, 1); break;
|
|
case 0xA000: VRC_VBANK(0, value, 0); break;
|
|
case 0xA001: VRC_VBANK(0, value, 1); break;
|
|
case 0xA002: VRC_VBANK(1, value, 0); break;
|
|
case 0xA003: VRC_VBANK(1, value, 1); break;
|
|
case 0xB000: VRC_VBANK(2, value, 0); break;
|
|
case 0xB001: VRC_VBANK(2, value, 1); break;
|
|
case 0xB002: VRC_VBANK(3, value, 0); break;
|
|
case 0xB003: VRC_VBANK(3, value, 1); break;
|
|
case 0xC000: VRC_VBANK(4, value, 0); break;
|
|
case 0xC001: VRC_VBANK(4, value, 1); break;
|
|
case 0xC002: VRC_VBANK(5, value, 0); break;
|
|
case 0xC003: VRC_VBANK(5, value, 1); break;
|
|
case 0xD000: VRC_VBANK(6, value, 0); break;
|
|
case 0xD001: VRC_VBANK(6, value, 1); break;
|
|
case 0xD002: VRC_VBANK(7, value, 0); break;
|
|
case 0xD003: VRC_VBANK(7, value, 1); break;
|
|
case 0xE000:
|
|
irq.nybbles[0]=value&0x0F;
|
|
irq.clockticks= (irq.nybbles[0]) | (irq.nybbles[1]<<4) |
|
|
(irq.nybbles[2]<<8) | (irq.nybbles[3]<<12);
|
|
irq.counter=(uint8)(irq.clockticks/114);
|
|
if(irq.counter>15) irq.counter-=16;
|
|
break;
|
|
case 0xE001:
|
|
irq.nybbles[1]=value&0x0F;
|
|
irq.clockticks= (irq.nybbles[0]) | (irq.nybbles[1]<<4) |
|
|
(irq.nybbles[2]<<8) | (irq.nybbles[3]<<12);
|
|
irq.counter=(uint8)(irq.clockticks/114);
|
|
if(irq.counter>15) irq.counter-=16;
|
|
break;
|
|
case 0xE002:
|
|
irq.nybbles[2]=value&0x0F;
|
|
irq.clockticks= (irq.nybbles[0]) | (irq.nybbles[1]<<4) |
|
|
(irq.nybbles[2]<<8) | (irq.nybbles[3]<<12);
|
|
irq.counter=(uint8)(irq.clockticks/114);
|
|
if(irq.counter>15) irq.counter-=16;
|
|
break;
|
|
case 0xE003:
|
|
irq.nybbles[3]=value&0x0F;
|
|
irq.clockticks= (irq.nybbles[0]) | (irq.nybbles[1]<<4) |
|
|
(irq.nybbles[2]<<8) | (irq.nybbles[3]<<12);
|
|
irq.counter=(uint8)(irq.clockticks/114);
|
|
if(irq.counter>15) irq.counter-=16;
|
|
break;
|
|
case 0xF000:
|
|
if(value&0x01) irq.enabled=true;
|
|
break;
|
|
case 0xF001:
|
|
irq.enabled=value&0x01;
|
|
break;
|
|
case 0xF002:
|
|
switch(value&0x03)
|
|
{
|
|
case 0: ppu_mirror(0, 0, 1, 1); break;
|
|
case 1: ppu_mirror(0, 1, 0, 1); break;
|
|
case 2: ppu_mirror(1,1,1,1);break;
|
|
case 3: ppu_mirror(1,1,1,1);break; // should this be zero?
|
|
default: break;
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
static const map_memwrite map18_memwrite[] =
|
|
{
|
|
{ 0x8000, 0xFFFF, map18_write },
|
|
{ -1, -1, NULL }
|
|
};
|
|
|
|
static void map18_getstate(SnssMapperBlock *state)
|
|
{
|
|
state->extraData.mapper18.irqCounterLowByte = irq.counter & 0xFF;
|
|
state->extraData.mapper18.irqCounterHighByte = irq.counter >> 8;
|
|
state->extraData.mapper18.irqCounterEnabled = irq.enabled;
|
|
}
|
|
|
|
static void map18_setstate(SnssMapperBlock *state)
|
|
{
|
|
irq.counter = (state->extraData.mapper18.irqCounterHighByte << 8)
|
|
| state->extraData.mapper18.irqCounterLowByte;
|
|
irq.enabled = state->extraData.mapper18.irqCounterEnabled;
|
|
}
|
|
|
|
const mapintf_t map18_intf =
|
|
{
|
|
18, /* mapper number */
|
|
"Jaleco SS8806", /* mapper name */
|
|
map18_init, /* init routine */
|
|
NULL, /* vblank callback */
|
|
NULL, /* hblank callback */
|
|
map18_getstate, /* get state (snss) */
|
|
map18_setstate, /* set state (snss) */
|
|
NULL, /* memory read structure */
|
|
map18_memwrite, /* memory write structure */
|
|
NULL /* external sound device */
|
|
};
|
|
|
|
/*
|
|
** $Log: map018.c,v $
|
|
** Revision 1.2 2001/04/27 14:37:11 neil
|
|
** wheeee
|
|
**
|
|
** Revision 1.1 2001/04/27 12:54:40 neil
|
|
** blah
|
|
**
|
|
** Revision 1.1.1.1 2001/04/27 07:03:54 neil
|
|
** initial
|
|
**
|
|
** Revision 1.1 2000/10/24 12:19:33 matt
|
|
** changed directory structure
|
|
**
|
|
** Revision 1.8 2000/10/22 19:17:46 matt
|
|
** mapper cleanups galore
|
|
**
|
|
** Revision 1.7 2000/10/22 15:03:13 matt
|
|
** simplified mirroring
|
|
**
|
|
** Revision 1.6 2000/10/21 19:33:38 matt
|
|
** many more cleanups
|
|
**
|
|
** Revision 1.5 2000/10/10 13:58:17 matt
|
|
** stroustrup squeezing his way in the door
|
|
**
|
|
** Revision 1.4 2000/07/15 23:52:19 matt
|
|
** rounded out a bunch more mapper interfaces
|
|
**
|
|
** Revision 1.3 2000/07/10 05:29:03 matt
|
|
** cleaned up some mirroring issues
|
|
**
|
|
** Revision 1.2 2000/07/06 02:48:42 matt
|
|
** clearly labelled structure members
|
|
**
|
|
** Revision 1.1 2000/07/06 01:01:56 matt
|
|
** initial revision
|
|
**
|
|
*/
|