HC-SR501 PIR with WeAct Black Pill STM32F411CE

Wiring for the HC-SR501 PIR motion sensor on the WeAct Black Pill STM32F411CE (STM32F411CE, 3.3 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

Check before you power it on

• Supply: 5 V from the 5V pin.
• The HC-SR501 PIR works at 5 V. On the WeAct Black Pill STM32F411CE, B12 tolerate 5 V inputs, so a direct connection is fine while the board is powered.

Test code (Arduino)

void setup() {
  Serial.begin(115200);
  pinMode(PB12, INPUT);  // OUT on B12
}

void loop() {
  Serial.println(digitalRead(PB12));
  delay(100);
}

Arduino board: STMicroelectronics:stm32:GenF4:pnum=BLACKPILL_F411CE,usb=CDCgen,upload_method=dfuMethod. To upload over USB, hold BOOT0, press and release NRST, then release BOOT0 (DFU mode). An ST-LINK on the SWD pins also works.

Questions

Which WeAct Black Pill STM32F411CE pins do I use for the HC-SR501 PIR?

VCC → 5V, OUT → B12 (PB12), GND → G.

Does the HC-SR501 PIR work with the WeAct Black Pill STM32F411CE at 3.3 V?

Yes: the HC-SR501 PIR runs at 5 V and the WeAct Black Pill STM32F411CE uses 3.3 V signals, so no level shifting is needed.

Full WeAct Black Pill STM32F411CE pinout · HC-SR501 PIR motion sensor: all pins and data

The HC-SR501 PIR on other boards

ESP32 DevKit Arduino Mega 2560 R3 Arduino Nano Arduino Uno R3 ESP32-C3-DevKitM-1 ESP32-S3-DevKitC-1 Nordic nRF52840 DK NUCLEO-F401RE Raspberry Pi Pico 2 Raspberry Pi Pico W Raspberry Pi Pico Teensy 4.1

Other parts on the WeAct Black Pill STM32F411CE

BME280 BMP280 DHT22 DHT11 HC-SR04 SSD1306 OLED MPU6050 DS18B20 WS2812B LED strip SG90 servo Relay module LCD 1602 I2C INA219 VL53L0X BH1750 MAX30102 RC522 RFID NEO-6M GPS Capacitive soil moisture sensor ADS1115 TM1637 28BYJ-48 stepper L298N Potentiometer Push button LED Joystick module SD card module AHT20