读写参考程序.txt

avr与PC机之间的通信

//output to D12 (write to D12)
void Output_D12(uchar Address,uchar Data)
{
 //*((uchar xdata *) Address) = Data;
 PORTD |=(1<<ALE); //SET ALE H
 DDRB=0xff;
 PORTB=Address; //load address
 NOP();
 PORTD &=~(1<<ALE); //RESET ALE L
 PORTB=Data;
 PORTC &=~(1<<D12WR); //Enalbe write
 NOP(); //waite some time 
 NOP();
 PORTC |=(1<<D12WR);
 
}


//input to MCU(read D12)
uchar Input_D12(uchar Address)
{
 //return *((uchar xdata *) Address);
 uchar temp;
 PORTD |=(1<<ALE); //SET ALE H
 DDRB=0xff ;

 PORTB=Address; //load address
 NOP();
 PORTD &=~(1<<ALE); //RESET ALE L
 DDRB=0x00;
 PORTB=0xff;  //
 PORTC &=~(1<<D12RD);

 NOP();
 temp=PINB;
 PORTC |=(1<<D12RD);
 return temp;

}