Detecting Motion Using the HC-SR501 Passive Infra-Red (PIR) Sensor and NodeMcu
The PIR sensor is used to detect movement in front of the sensor. The sensor, which is coded as “HC-SR501” on the market, is made of pyroelectric material that can detect infrared radiation. The PIR sensor works by capturing infrared rays, then it will enter through the Fresnel lens and hit the pyroelectric sensor, infrared … Read more