HC-SR501 PIR with Arduino Uno R3

Wiring for the HC-SR501 PIR motion sensor on the Arduino Uno R3 (ATmega328P, 5 V logic), chosen with the same pin rules BoardPilot uses: default buses first, and no pins that are used for flash, USB, the debugger or booting.

Wiring

HC-SR501 PIR pinRoleArduino Uno R3 pinNotes
VCCPower5VNeeds 4.5 V or more: use 5V
OUTOutput from the part2 (PD2)
GNDGroundGND

Check before you power it on

Test code (Arduino)

void setup() {
  Serial.begin(115200);
  pinMode(2, INPUT);  // OUT on 2
}

void loop() {
  Serial.println(digitalRead(2));
  delay(100);
}

Arduino board: arduino:avr:uno.

Questions

Which Arduino Uno R3 pins do I use for the HC-SR501 PIR?

VCC → 5V, OUT → 2 (PD2), GND → GND.

Does the HC-SR501 PIR work with the Arduino Uno R3 at 5 V?

Yes: the HC-SR501 PIR runs at 5 V and the Arduino Uno R3 uses 5 V signals, so no level shifting is needed.

BoardPilot checks this wiring in 3D as you build it, and finds crossed or missing wires on the real board.

Download BoardPilot

Full Arduino Uno R3 pinout · HC-SR501 PIR motion sensor: all pins and data

The HC-SR501 PIR on other boards

Other parts on the Arduino Uno R3