Motion detection using Raspberry Pi and a PIR

main.go

package main

import (
	"flag"
	"fmt"
	"os"
	"time"

	"github.com/stianeikeland/go-rpio"
)

func main() {
	//	Defaults to GPIO pin 23 (NOT physical pin 23)
	//	but you can pass any pin
	//	See https://pinout.xyz for more information on GPIO pin layout
  //  Need a PIR sensor?  I used this one: https://www.adafruit.com/product/189
	pinNumber := flag.Int("pin", 23, "GPIO pin")
	flag.Parse()

	if err := rpio.Open(); err != nil {
		fmt.Println(err)
		os.Exit(1)
	}
	defer rpio.Close()

	pin := rpio.Pin(*pinNumber)
	pin.Mode(rpio.Input)

	//	Store the 'last reading'
	//	Initially, set it to the 'low' (no motion) state
	lr := rpio.Low

	//	The big loop
	for {
		//	Read from the sensor
		v := pin.Read()

		//	Latch / unlatch check
		if lr != v {
			lr = v
			if lr == rpio.High {
				fmt.Printf("Motion detected!\n")
			}
			if lr == rpio.Low {
				fmt.Printf("Motion reset\n")
			}
		}

		//	Sleep for a second
		time.Sleep(time.Millisecond * 100)
	}
}