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#include "nsf_emu.h"
#ifndef NSF_EMU_APU_ONLY
#include "nes_namco_apu.h"
#include "nes_fds_apu.h"
#include "nes_mmc5_apu.h"
#endif
#include "blargg_source.h"
int Cpu_read( struct Nsf_Emu* this, nes_addr_t addr )
{
int result = this->cpu.low_mem [addr & 0x7FF];
if ( addr & 0xE000 )
{
result = *Cpu_get_code( &this->cpu, addr );
if ( addr < sram_addr )
{
if ( addr == status_addr )
result = Apu_read_status( &this->apu, Cpu_time( &this->cpu ) );
else
{
#ifndef NSF_EMU_APU_ONLY
if ( namco_enabled( this ) && addr == namco_data_reg_addr )
return Namco_read_data( &this->namco );
if ( fds_enabled( this ) && (unsigned) (addr - fds_io_addr) < fds_io_size )
return Fds_read( &this->fds, Cpu_time( &this->cpu ), addr );
if ( mmc5_enabled( this ) ) {
int i = addr - 0x5C00;
if ( (unsigned) i < mmc5_exram_size )
return this->mmc5.exram [i];
int m = addr - 0x5205;
if ( (unsigned) m < 2 )
return (this->mmc5_mul [0] * this->mmc5_mul [1]) >> (m * 8) & 0xFF;
}
#endif
result = addr >> 8; // simulate open bus
}
}
}
/* if ( addr != 0x2002 )
debug_printf( "Read unmapped $%.4X\n", (unsigned) addr ); */
return result;
}
void Cpu_write( struct Nsf_Emu* this, nes_addr_t addr, int data )
{
int offset = addr - sram_addr;
if ( (unsigned) offset < sram_size )
{
this->sram [offset] = data;
}
else
{
// after sram because cpu handles most low_ram accesses internally already
int temp = addr & (low_ram_size-1); // also handles wrap-around
if ( !(addr & 0xE000) )
{
this->cpu.low_mem [temp] = data;
}
else
{
int bank = addr - banks_addr;
if ( (unsigned) bank < bank_count )
{
Write_bank( this, bank, data );
}
else if ( (unsigned) (addr - start_addr) <= end_addr - start_addr )
{
Apu_write_register( &this->apu, Cpu_time( &this->cpu ), addr, data );
}
else
{
#ifndef NSF_EMU_APU_ONLY
// 0x8000-0xDFFF is writable
int i = addr - 0x8000;
if ( fds_enabled( this ) && (unsigned) i < fdsram_size )
fdsram( this ) [i] = data;
else
#endif
Cpu_write_misc( this, addr, data );
}
}
}
}
#define CPU_READ( emu, addr, time ) Cpu_read( emu, addr )
#define CPU_WRITE( emu, addr, data, time ) Cpu_write( emu, addr, data )
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