f40bfc9267
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97 Reviewed-on: http://gerrit.rockbox.org/137 Reviewed-by: Nils Wallménius <nils@rockbox.org> Tested-by: Nils Wallménius <nils@rockbox.org>
61 lines
1.3 KiB
C
61 lines
1.3 KiB
C
// NES MMC5 sound chip emulator
|
|
|
|
// Nes_Snd_Emu 0.2.0-pre
|
|
#ifndef NES_MMC5_APU_H
|
|
#define NES_MMC5_APU_H
|
|
|
|
#include "blargg_common.h"
|
|
#include "nes_apu.h"
|
|
|
|
enum { mmc5_regs_addr = 0x5000 };
|
|
enum { mmc5_regs_size = 0x16 };
|
|
enum { mmc5_osc_count = 3 };
|
|
enum { mmc5_exram_size = 1024 };
|
|
|
|
struct Nes_Mmc5_Apu {
|
|
struct Nes_Apu apu;
|
|
unsigned char exram [mmc5_exram_size];
|
|
};
|
|
|
|
static inline void Mmc5_init( struct Nes_Mmc5_Apu* this )
|
|
{
|
|
Apu_init( &this->apu );
|
|
}
|
|
|
|
static inline void Mmc5_set_output( struct Nes_Mmc5_Apu* this, int i, struct Blip_Buffer* b )
|
|
{
|
|
// in: square 1, square 2, PCM
|
|
// out: square 1, square 2, skipped, skipped, PCM
|
|
if ( i > 1 )
|
|
i += 2;
|
|
Apu_osc_output( &this->apu, i, b );
|
|
}
|
|
|
|
static inline void Mmc5_write_register( struct Nes_Mmc5_Apu* this, blip_time_t time, unsigned addr, int data )
|
|
{
|
|
switch ( addr )
|
|
{
|
|
case 0x5015: // channel enables
|
|
data &= 0x03; // enable the square waves only
|
|
// fall through
|
|
case 0x5000: // Square 1
|
|
case 0x5002:
|
|
case 0x5003:
|
|
case 0x5004: // Square 2
|
|
case 0x5006:
|
|
case 0x5007:
|
|
case 0x5011: // DAC
|
|
Apu_write_register( &this->apu, time, addr - 0x1000, data );
|
|
break;
|
|
|
|
case 0x5010: // some things write to this for some reason
|
|
break;
|
|
|
|
#ifdef BLARGG_DEBUG_H
|
|
default:
|
|
dprintf( "Unmapped MMC5 APU write: $%04X <- $%02X\n", addr, data );
|
|
#endif
|
|
}
|
|
}
|
|
|
|
#endif
|