71 lines
1.5 KiB
C
71 lines
1.5 KiB
C
|
// NES MMC5 sound chip emulator
|
||
|
|
||
|
// Nes_Snd_Emu $vers
|
||
|
#ifndef NES_MMC5_APU_H
|
||
|
#define NES_MMC5_APU_H
|
||
|
|
||
|
#include "blargg_common.h"
|
||
|
#include "Nes_Apu.h"
|
||
|
|
||
|
class Nes_Mmc5_Apu : public Nes_Apu {
|
||
|
public:
|
||
|
enum { regs_addr = 0x5000 };
|
||
|
enum { regs_size = 0x16 };
|
||
|
|
||
|
enum { osc_count = 3 };
|
||
|
void write_register( blip_time_t, unsigned addr, int data );
|
||
|
void set_output( Blip_Buffer* );
|
||
|
void set_output( int index, Blip_Buffer* );
|
||
|
|
||
|
enum { exram_size = 1024 };
|
||
|
unsigned char exram [exram_size];
|
||
|
|
||
|
BLARGG_DEPRECATED_TEXT( enum { start_addr = 0x5000 }; )
|
||
|
BLARGG_DEPRECATED_TEXT( enum { end_addr = 0x5015 }; )
|
||
|
};
|
||
|
|
||
|
inline void Nes_Mmc5_Apu::set_output( int i, Blip_Buffer* b )
|
||
|
{
|
||
|
// in: square 1, square 2, PCM
|
||
|
// out: square 1, square 2, skipped, skipped, PCM
|
||
|
if ( i > 1 )
|
||
|
i += 2;
|
||
|
Nes_Apu::set_output( i, b );
|
||
|
}
|
||
|
|
||
|
inline void Nes_Mmc5_Apu::set_output( Blip_Buffer* b )
|
||
|
{
|
||
|
set_output( 0, b );
|
||
|
set_output( 1, b );
|
||
|
set_output( 2, b );
|
||
|
}
|
||
|
|
||
|
inline void Nes_Mmc5_Apu::write_register( 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
|
||
|
Nes_Apu::write_register( 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
|