Hi all,
I was learning the arduino interrupts, and I'm facing a weird issue. This is how I reproduce it.
I configured interrupt(1) on digital pin 3.
In the code I attach the RISING interrupt when arduino receives character 'a'. The ISR is a simple function which prints "AAA" string.
In the code I detach the interrupt when arduino receives character 'b'.
So, from serial data transfer I can manually attach and detach the interrupt.
I connected a switching button to the pin 3. I also connected a 10k pulldown resistor.
When I attach the interrupt by sending 'a', and when I press the button I receive the "AAA".
When I detach the interrupt by sending 'b', and when I press the button I don't receive the "AAA".
Here everything is OK.
Now. When I attach the interrupt back again by sending 'a', I automatically receive "AAA", although I didn't press the button. It means an interrupt occurs, but I cannot understand why.
When I do not press the button when interrupt is detached, and I attach the interrupt, then everything is OK. The weird things happen only when I press the button when the interrupt is detached.
Did anyone also faced this phenomena? Is it a normal behavior?
The code I used is below:
void setup() {
pinMode(3, INPUT); //pin 3 for interrupt
Serial.begin(9600);
}
void loop() {
if (Serial.available()>0)
{
switch (Serial.read())
{
case 'a':
attachInterrupt(1,pulses_in,RISING);
break;
case 'b':
detachInterrupt(1);
break;
}
}
}
void pulses_in()
{
Serial.println("AAA");
}
Thanks in advance.
Gevorg
Figuring it out by modifying his code probably took the same number of minutes that it takes to search the source in the Arduino directory for "attachInterrupt".