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Unexpected digitalWrite behavior when writing numerical values 4 and 2 #145

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@SaltlessLemons

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@SaltlessLemons

Using digitalWrite(pin, 0b10) sets the pin high as expected unless it is preceded by a digitalWrite(pin, 0b100), in which case writing 0b10 actually sets the pin low. Subsequent writes (including reattempting to write 0b10) behave as expected.

Recreated in a new blank sketch, using an UNO Wifi R2 and Arduino IDE 2.3.6

#define PIN_LED 25 //Wifi R2 built-in LED is on pin 25

void setup() {
  //digitalWrite weird behaviour test
  pinMode(PIN_LED, OUTPUT);
  delay(2000);
  digitalWrite(PIN_LED, 0b100);
  delay(1000);
  digitalWrite(PIN_LED, 0b10); //LED Turns off here; removing the above write causes this write to behave as expected
  delay(1000);
  digitalWrite(PIN_LED, 0b1);
}

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

}

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          Unexpected digitalWrite behavior when writing numerical values 4 and 2 · Issue #145 · arduino/ArduinoCore-megaavr