Signal input to output

signal_input_to_output.c

/**
 * 
 * @file main.h
 * @brief main code for signal input to output
 *
 * @version 1.0.0
 * 
 * @author Walid Amriou
 * @date 23/09/2021
 * 
 */


#include <avr/io.h>
#include <util/delay.h>
#include <avr/interrupt.h>

// handler of external Interrupt 4 of pin E4
uint8_t pinstatus = 0;

ISR(INT4_vect) {
    // change status of pin 7 (13 in arduino uno)
    pinstatus=!pinstatus;
     digitalWrite(9, pinstatus);
    
}

// config external interrupt 4 of pin 2 
void initInterrupt4(void) { 
    EIMSK |= (1 << INT4); // (External Interrupt Mask Register) controls whether the INT0 and INT1 interrupts are enabled, here control INT0
    EICRA |= (1 << ISC40); // External Interrupt Control Register A, Defines the type of signals that activates the external Interrupt, here set INT0 to trigger on any change
    //EICRA |= (1 << ISC01); // set INT0 to trigger on falling edge
    // EICRA |= (1 << ISC01 || 1 << ISC00); // set INT0 to trigger on rising edge
    sei(); // a macro that executes an assembler instruction to enable interrupts.
}



void setup() {
  // put your setup code here, to run once:
    // make pin 2 output 
    DDRH |= (1<<6); // for PB1, and it means DDRB = DDRB | 0b00000010
    // 
    PORTE &= ~(1 << 4); // pullup

    initInterrupt4();
}

void loop() {
  // put your main code here, to run repeatedly:
  //delay(200);

}