Program error

Forum 2005-2010 (read only) Software Syntax & Programs
1

i am using the Arduino Duemilanaove Atmega 328
I am trying to send set up an interrupt to switch between routines.
5V signals are sent to the digitals as interupt signals.
I have used the 5V power supply from the board as the signal source.
I simply connected the output to input ports via a wire.

the code does not seem to switch between the routines when I pull the wire in and out (0V and 5V).

Is there a problem with my code or is it the way that I have connected the 5V signal.
The following is the code I used:

int pin = 13;
int inputpin = 2;
int sequence = 0;

void sub(){
sequence++;
if (sequence == 2) {
sequence = 0;
}
}

void setup() {

pinMode(pin, OUTPUT);
pinMode(inputpin, INPUT);
attachInterrupt(inputpin, sub, CHANGE);
}

void loop() {

if (sequence == 0) {
digitalWrite(pin, LOW);
}
else if (sequence == 1) {
digitalWrite(pin, HIGH);
}
}

2

Hi tonyfeng03;

Try to use the # when posting code (it is in the toolbar above the edit box in the post window) It makes things easier to look at.

For your problem; The compiler may have been optimizing the variables. Try to add the volatile keyword in your declaration, like this:

volatile int sequence = 0;