Hi, I was trying this code to blink the LED on pin 13.
const int led_pin = PB5;
void setup () {
DDRB |= (1 << led_pin); // set led_pin to be output
}
void loop () {
PORTB ^= (1 << led_pin);
delay(1000);}
This code works, but I don’t understand what happens on the register PORTB. The processor flips the register after the delay ?
:
Well normally the AND ^ don’t flip the bit on position 13. 1 ^ 1 = 1 and 0 ^ 1 = 0. Why the led blinks ?
Thank you ;D
killwin:
Well normally the AND ^ don't flip the bit on position 13. 1 ^ 1 = 1 and 0 ^ 1 = 0. Why the led blinks ?
That is because a bitwise AND is & The ^ is an exclusive-or.
https://www.arduino.cc/reference/en/language/structure/bitwise-operators/bitwisexor/
killwin:
Hi, I was trying this code to blink the LED on pin 13.This code works, but I don't understand what happens on the register PORTB. The processor flips the register after the delay ?
before the delay...
:
Well normally the AND ^ don't flip the bit on position 13. 1 ^ 1 = 1 and 0 ^ 1 = 0. Why the led blinks ?
Thank you ;D
1 ^ 1 == 0
1 ^ 0 == 1
0 ^ 1 == 1
0 ^ 0 == 0
