ATtiny85 ควบคุม 7-Segment ด้วย 74HC595 (Shift Register)

/*

* Counter.cpp

*

* Created: 12.04.2013 14:12:59

*  Author: Jopi

*/

#include <avr/io.h>

#include <util/delay.h>

#include <avr/interrupt.h>

#define LATCH_PIN PB4

#define SHIFT_PIN PB1

#define DATA_PIN PB0

#define BUTTON_PIN PB2 //PB2 is INT0

uint8_t digits[10] = {

 0b00111111,

0b00001100,

0b01101011,

0b01101101,

0b01011100,

0b01110101,

0b01110111,

0b00101100,

0b01111111,

0b01111101

};

uint8_t rightDigit = 0;

uint8_t leftDigit = 0;

void latch() {

//Set the Latch clock pin to low

PORTB &= ~(1<<LATCH_PIN);

//Set latch pin back to high -> shift register will copy buffer to latch register

PORTB |= 1<<LATCH_PIN;

}

void shiftOut(uint8_t data) {

for(uint8_t i = 0; i < 8; i++) {

bool state = !((data & (1 << i )) != 0);

//bool state = bit_is_clear(PINB, 1);

if(state) {

//set high signal

PORTB |= 1 << DATA_PIN;

} else { //low or different than 1

//set low signal

PORTB &= ~(1<< DATA_PIN);

}

//pulse shift clock pin -> shift register will shift the current bit in

PORTB |= 1 << SHIFT_PIN;

PORTB &= ~(1<< SHIFT_PIN);

}

return;

}

void incrementCounter(){

if(rightDigit == 9) { //check if left digit has to be incremented

if(leftDigit == 9) { //99; reset

leftDigit = 0;

rightDigit = -1; //will be set to 0 later by incrementing

} else { //left digit < 9

leftDigit += 1;

rightDigit = -1; //will be set to 0 later by incrementing

}

}

rightDigit += 1;

}

void shiftCounter() {

shiftOut(digits[rightDigit]);

shiftOut(digits[leftDigit]);

latch();

}

int main(void)

{

//Set PB0 to Output

DDRB = 0b11; //PB0-1 Output

DDRB |= (1 << LATCH_PIN); //Set Latch Pin to Output

//Set Button Pin to Input & HIGH

DDRB &= ~(1 << BUTTON_PIN);

PORTB |= 1 << BUTTON_PIN;

//Set Interrupt for PB2 (INT0)

//Falling Edge:

MCUCR |= 1 << ISC01; //ISC01 to 1

MCUCR &= ~(1 << ISC00); //ISC00 to 0

//Activate Interrupt INT0

GIMSK |= 1 << INT0;

//Activate Interrupts

sei();

//int out[8] = {0, 0, 0, 0, 0, 0, 0, 1}; //Last bit equals Q0, which won't be used for this project

   while(1)

   {

//for(uint8_t i = 0; i < 100; i++) { // 0 - 99

//incrementCounter();

//

//shiftCounter();

//

//_delay_ms(500);

//}

   }

}

ISR(INT0_vect) {

incrementCounter();

shiftCounter();

}