HW-456 PIR Motion Sensor Module

Lines 1 - 2 import the necessary dependencies for the code to run.

• The Pin module lets our code communicate with the hardware.
• The sleep function lets us pause the code for a specified number of seconds.
• The localtime function lets us get the current time as an 8-tuple.

from machine import Pin 
from time import sleep, localtime 
 
signalPin = Pin(0, Pin.IN)
 
def formatTime(timeArray):
    h = timeArray[3]
    m = timeArray[4]
    s = timeArray[5]
    return ":".join([str(h),str(m),str(s)])
 
while True:
  if signalPin.value()==1:
    print(formatTime(localtime()), "Movement detected.")
  else:
    print("------")
  sleep(1)

Line 4 instantiates the signalPin object which is how the Pico and the HW-456 will communicate.

The first argument is the pin number on the Pico. In this example we use pin 0, which refers to GP0 on the Pico (physical pin 1). You can use any GPIO pin you want, just make sure to reference the correct pin number in the code. Here's the pinout diagram

The second argument is the mode of the pin. In this case, we want to read the signal from the HW-456, so we set the mode to Pin.IN.

from machine import Pin
from time import sleep, localtime
 
signalPin = Pin(0, Pin.IN) 
 
def formatTime(timeArray):
    h = timeArray[3]
    m = timeArray[4]
    s = timeArray[5]
    return ":".join([str(h),str(m),str(s)])
 
while True:
  if signalPin.value()==1:
    print(formatTime(localtime()), "Movement detected.")
  else:
    print("------")
  sleep(1)

Lines 6 - 10 define a function called formatTime which takes an 8-tuple as an argument and returns a string in the format HH:MM:SS.

This is not strictly necessary for the function of this code, but I wanted to see time stamps to help differentiate the otherwise identical and repetitive messages.

There may be a more elegant way to do this, but Python is not my expertise.

from machine import Pin
from time import sleep, localtime
 
signalPin = Pin(0, Pin.IN)
 
def formatTime(timeArray): 
    h = timeArray[3] 
    m = timeArray[4] 
    s = timeArray[5] 
    return ":".join([str(h),str(m),str(s)]) 
 
while True:
  if signalPin.value()==1:
    print(formatTime(localtime()), "Movement detected.")
  else:
    print("------")
  sleep(1)

Lines 12 - 16 use an infinite while loop to check the value of the signal pin every second. It will run indefinitely until you terminate the code manually.

Each iteration of the loop checks the value of the signal pin using the value() method. If the value is 1, the code prints the current time and a message indicating motion was detected.

If no motion is detected, then the value of the signal pin is 0, and the else block prints a series of dashes to indicate no motion was detected. This else block is not strictly necessary, but I wanted to see a visual indication of the lack of motion.

Finally line 17 pauses the code for 1 second before the next iteration of the loop. You can adjust this value to make the code run faster or slower to suit your needs.

from machine import Pin
from time import sleep, localtime
 
signalPin = Pin(0, Pin.IN)
 
def formatTime(timeArray):
    h = timeArray[3]
    m = timeArray[4]
    s = timeArray[5]
    return ":".join([str(h),str(m),str(s)])
 
while True: 
  if signalPin.value()==1: 
    print(formatTime(localtime()), "Movement detected.") 
  else: 
    print("------") 
  sleep(1)