map087.c
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/*
** 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.
**
**
** map087.c
**
** Mapper #87 (16K VROM switch)
** Implementation by Firebug
** $Id: map087.c,v 1.2 2001/04/27 14:37:11 neil Exp $
**
*/
#include <noftypes.h>
#include <nes_mmc.h>
#include <nes.h>
#include <libsnss.h>
#include <log.h>
/******************************************/
/* Mapper #87 write handler ($6000-$7FFF) */
/******************************************/
static void map87_write (uint32 address, uint8 value)
{
/* Within range, address written to is irrelevant */
UNUSED (address);
/* Very simple: 8K CHR page is selected by D1 */
if (value & 0x02) mmc_bankvrom (8, 0x0000, 0x01);
else mmc_bankvrom (8, 0x0000, 0x00);
/* Done */
return;
}
static map_memwrite map87_memwrite [] =
{
{ 0x6000, 0x7FFF, map87_write },
{ -1, -1, NULL }
};
mapintf_t map87_intf =
{
87, /* Mapper number */
"16K VROM switch", /* Mapper name */
NULL, /* Initialization routine */
NULL, /* VBlank callback */
NULL, /* HBlank callback */
NULL, /* Get state (SNSS) */
NULL, /* Set state (SNSS) */
NULL, /* Memory read structure */
map87_memwrite, /* Memory write structure */
NULL /* External sound device */
};
/*
** $Log: map087.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 2001/04/27 10:57:41 neil
** wheee
**
** Revision 1.1 2000/12/30 06:34:44 firebug
** Initial revision
**
**
*/