[Atmega128] 2bit FND, 74hc595, Atmega128

/*

PORTA.0 = Data DS

PORTA.1 = Latch STCP

PORTA.2 = Shift SHCP

*/

#define F_CPU 16000000UL

#include <avr/io.h>

#include <util/delay.h>

void HC595write(unsigned char udata){

unsigned char i;

i = 7;

while(i<=7){

PORTA = (udata >> i) & 0x01;// DATA

PORTA |= 0b00000100; // SHIFT 1

PORTA &= 0b11111011; // SHIFT 0

i--;

}

}

void HC595write_2byte(unsigned int udata){

unsigned char digit[10] = {

0b11111100, //0

0b01100000, //1

0b11011010, //2

0b11110010, //3

0b01100110, //4

0b10110110, //5

0b00111110, //6

0b11100100, //7

0b11111110, //8

0b11100110 //9

};

PORTA &= 0b11111110; // DATA 0

PORTA &= 0b11111011; // SHIFT 0

PORTA &= 0b11111101; // LATCH 0

unsigned char d10 = digit[udata/10];

unsigned char d1  = digit[udata%10];

HC595write(~d10);

HC595write(~d1);

PORTA |= 0b00000010; // LATCH 0

PORTA &= 0b11111101; // LATCH 1

}

int main(void){

DDRA = 0xFF;

unsigned int num_buf = 0;

while(1){

HC595write_2byte(num_buf);

_delay_ms(200);

num_buf++;

if(num_buf>99) num_buf = 0;

}

}