Use a Sparkfun COM-14662 12 digit 3*4 matrix keypad with a Raspberry Pi for PIR alarm system

Download PDF version of this guide at http://www.securipi.co.uk/keypad.pdf

The keypad we used is a Sparkfun Electronics COM14662 which is available from Pimoroni in the UK for £3.50. Similar looking keypads are available on Aliexpress.com https://www.aliexpress.com/item/12-Key-Membrane-Switch-Keypad-4-x-3-Matrix-Array-Matrix-keyboard-membrane-switch-keypad/32824251000.html for $2.20

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This next image shows you how the keypad is wired internally

 

 

 

 

 

 

 

 

The examples use the same GPIO pins as Sparkfun Electronics COM14662. If you’re using a different keypad you’ll need to look at the documentation and maybe make changes.

The Python code uses the Raspberry Pi’s internal pull-up resistors, otherwise you’d need a 10k resistor on each col line to stop the GPIO 4/17/22 inputs floating around between 1 and 0.

The software that figures out which button was pressed first scans all the col lines for an input and then switches the GPIO inputs around and scans the row lines instead, to determine exactly which key was pressed. Fortunately there’s some existing Python code to do this for us:

http://crumpspot.blogspot.com/2013/05/using-3×4-matrix-keypad-with-raspberry.html

matrixKeypad_RPi_GPIO.py

matrixKeypad_test.py

I cut and pasted both examples into a nano editor session and saved them, but they’re also in our demo zip file. You can get that with:

wget www.securipi.co.uk/keypad.zip

unzip keypad.zip

You can run the demo with

python matrixKeypad_test.py

and you’ll be able to enter a 4 digit pin and see it printed.

We also built our own working alarm system demo using a PIR movement sensor connected to pins 5V, GND and GPIO8 which you can run with

python alarm2.py

This script lets you input a 4 digit pin. If you enter the correct pin, which is 5678, then the alarm will arm. Once the alarm is armed, any movement detected by the PIR will print a movement detected message to the console. There are other scripts that build on this to email you a photo of the intruder and write the time and date of PIR alerts to a log file.

from matrixKeypad_RPi_GPIO import keypad
from time import sleep
import RPi.GPIO as GPIO
import os

digitCount = 0
pin = [0,0,0,0]
finalPin = "0000"
validPin = "5678"
armState = 0
pirPin = 8

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(pirPin, GPIO.IN)

# Initialize the keypad class
kp = keypad()

def digitreturn():
    # Loop while waiting for a keypress
    r = None
    while r == None:
        r = kp.getKey()
        pirtest()
    return r

def message():
    os.system('clear')
    print("Please enter a 4 digit pin using the keypad")

def pirtest():
    if GPIO.input(pirPin) and armState == 1:
        print("Movement Detected. Intruders!")
        sleep(3)
message()

while True:
    digit = digitreturn()
    print digit
    pin[digitCount] = digit
    digitCount = digitCount + 1
    sleep(0.25)
    if digitCount == 4:
        finalPin = (str(pin[0]) + str(pin[1]) + str(pin[2]) + str(pin[3]))
        print(finalPin)
        if validPin == finalPin:
            print("You entered the correct PIN")
            if armState == 0:
                print("alarm will arm in 5 seconds, get out now")
                sleep(5)
                print("armed")
                armState = 1
                sleep(1)
                message()
            elif armState == 1:
                print("alarm is now disarmed")
                armState = 0
        digitCount = 0

and this version will take a time and date stamped photo of the intruder for you

import picamera
from matrixKeypad_RPi_GPIO import keypad
from time import sleep
import RPi.GPIO as GPIO
import os
import datetime

digitCount = 0
pin = [0,0,0,0]
finalPin = "0000"
validPin = "5678"
armState = 0
pirPin = 8
camera = picamera.PiCamera()

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(pirPin, GPIO.IN)

# Initialize the keypad class
kp = keypad()

def digitreturn():
    # Loop while waiting for a keypress
    r = None
    while r == None:
        r = kp.getKey()
        pirtest()
    return r

def message():
    os.system('clear')
    print("Please enter a 4 digit pin using the keypad")

def pirtest():
    if GPIO.input(pirPin) and armState == 1:
        now = datetime.datetime.now().strftime("%y-%m-%d--%H-%M-%S")
        print("Movement Detected " + now + ".  Taking a photo")
        camera.start_preview()
        sleep(3)
        camera.annotate_background = picamera.Color('black')
        camera.annotate_text = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
        camera.capture('/home/pi/' + now + 'image.jpg')
        camera.stop_preview()


message()

while True:
    digit = digitreturn()
    print digit
    pin[digitCount] = digit
    digitCount = digitCount + 1
    sleep(0.25)
    if digitCount == 4:
        finalPin = (str(pin[0]) + str(pin[1]) + str(pin[2]) + str(pin[3]))
        print(finalPin)
        if validPin == finalPin:
            print("You entered the correct PIN")
            if armState == 0:
                print("alarm will arm in 5 seconds, get out now")
                sleep(5)
                print("armed")
                armState = 1
                sleep(1)
                message()
            elif armState == 1:
                print("alarm is now disarmed")
                armState = 0
        digitCount = 0

This version will send you a photo of the intruder as an email attachment

import picamera
from matrixKeypad_RPi_GPIO import keypad
from time import sleep
import RPi.GPIO as GPIO
import os
import datetime

#email setup below
from email.MIMEMultipart import MIMEMultipart
from email.MIMEText import MIMEText
from email.MIMEImage import MIMEImage
import smtplib


digitCount = 0
pin = [0,0,0,0]
finalPin = "0000"
validPin = "5678"
armState = 0
pirPin = 8
camera = picamera.PiCamera()

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(pirPin, GPIO.IN)

# Initialize the keypad class
kp = keypad()

def digitreturn():
    # Loop while waiting for a keypress
    r = None
    while r == None:
        r = kp.getKey()
        pirtest()
    return r

def message():
    os.system('clear')
    print("Please enter a 4 digit pin using the keypad")

def pirtest():
    if GPIO.input(pirPin) and armState == 1:
        now = datetime.datetime.now().strftime("%y-%m-%d--%H-%M-%S")
        print("Movement Detected " + now + ".  Taking a photo")
        camera.start_preview()
        sleep(3)
        camera.annotate_background = picamera.Color('black')
        camera.annotate_text = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
        camera.capture('/home/pi/' + now + 'image.jpg')
        camera.stop_preview()
        # Send an email section. Make a new gmail account just for your Pi to use.  Then enable "less secure apps"
        # https://www.google.com/settings/u/0/security/lesssecureapps
        msg = MIMEMultipart()
        msg.attach(MIMEImage(file('/home/pi/' + now + 'image.jpg').read()))
        mailer = smtplib.SMTP('smtp.gmail.com:587')
        mailer.starttls()
        # Login and password of your new gmail address go here
        mailer.login("myraspberrypi","password")
        # Recipient is the regular email account on your phone or PC.
        mailer.sendmail("myraspberrypi@gmail.com", ["recipient@gmail.com"], msg.as_string())
        mailer.close()

message()

while True:
    digit = digitreturn()
    print digit
    pin[digitCount] = digit
    digitCount = digitCount + 1
    sleep(0.25)
    if digitCount == 4:
        finalPin = (str(pin[0]) + str(pin[1]) + str(pin[2]) + str(pin[3]))
        print(finalPin)
        if validPin == finalPin:
            print("You entered the correct PIN")
            if armState == 0:
                print("alarm will arm in 5 seconds, get out now")
                sleep(5)
                print("armed")
                armState = 1
                sleep(1)
                message()
            elif armState == 1:
                print("alarm is now disarmed")
                armState = 0
        digitCount = 0

The Senior Guardian project uses a PIR motion sensor to discretely keep an eye on an older vulnerable relative who lives alone.

Each time a person walks past the PIR sensor it adds one to the number of movements detected that hour. It stores the number of movements detected each hour in a Python list and can send an email to your PC or phone that looks like this:

If you didn’t see any PIR detections at times you’d normally expect them to be up & around, then you could call them up to check everything’s okay or get a neighbour to check on them.

The PIR sensor attaches on GPIO pin 4 and is wired up like this:

or you could use one of our PIR Adapter Clips if you don’t want to use cables.

This version of the Python script (pir5.py) emails a copy of today’s log to two different email addresses once an hour (there are other variations in our download)

Download our free PDF Guide : Senior Guardian PDF guide

Download the Senior Guardian scripts direct to your Pi with

wget www.securipi.co.uk/sg.zip
unzip sg.zip

Buy a PIR with Cables and GPIO pin card £3

Buy a PIR Alarm kit for Raspberry Pi £11.99

To make this security camera project you’ll need:

• Raspberry Pi Zero W
• Raspberry Pi camera module
• SG90 micro servo
• Micro SD card with latest Raspbian Jessie
• 3D printed bracket and base
• 8x Nylon M2 nuts and bolts
• 20x 2p coins to weight the base down

The STL files to print the brackets are at www.securipi.co.uk/twistcam.zip

and you can edit the original files at:

https://www.tinkercad.com/things/jSjNEIT4z5V-twistcam-base-4-raspberry-pi-zero-w-and-servo-cctv-surveiilance

https://www.tinkercad.com/things/i6WyzsOBSMX-twistcam-using-raspberry-pi-zero-w-and-servo-cctv-surveiilance

Before attaching the Raspberry Pi and camera to the 3D printed parts, it’s a good idea to do the following at the Desktop -> Preferences ->Raspberry Pi Configuration:

• Enable SSH
• Change passwords for Pi and Root users to something secure and hard to guess.
• Enable the camera
• Boot to CLI

Reboot the Pi and login to the terminal

sudo iwlist wlan0 scan

will show WiFi routers near your Pi

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

and add these lines at the bottom, using your routers SSID name and password

network={
ssid="testing"
psk="testingPassword"
}

Save the file, exit and reboot your Pi. It should now auto-attach to your wireless network when it boots up.

The servo wires can be soldered directly in place, or use a Pimoroni GPIO hammer header and cables instead.

Assemble all the parts together

We’re using the open-source ServoBlaster code to control the servo from the BASH command line.

We install it like this:

mkdir twistcam

cd twistcam

wget https://raw.githubusercontent.com/richardghirst/PiBits/master/ServoBlaster/user/servod.c

wget https://raw.githubusercontent.com/richardghirst/PiBits/master/ServoBlaster/user/Makefile

wget https://raw.githubusercontent.com/richardghirst/PiBits/master/ServoBlaster/user/init-script

wget https://raw.githubusercontent.com/richardghirst/PiBits/master/ServoBlaster/user/mailbox.c

wget https://raw.githubusercontent.com/richardghirst/PiBits/master/ServoBlaster/user/mailbox.h

make servod

sudo ./servod

Then test it’s working with:

echo 5=50% > /dev/servoblaster

echo 5=10% > /dev/servoblaster

echo 5=90% > /dev/servoblaster

The commands above move servo number 5 (Pan left & right) on GPIO23 between centre (50%),
left (10%) & right (90%) positions

Setup Video Streaming to a web browser.

On your Raspberry Pi, while in the twistcam folder we made earlier:

sudo apt-get install libav-tools git python3-picamera python3-ws4py

Download the zip file with:

wget http://www.securipi.co.uk/tcs.zip

unzip tcs.zip

chmod a+x *.sh

python3 server.py

Then go to another PC on your network and open a web browser to:

http://ip-address-of-your-pi:8082/

And you should be able to pan the camera left and right using the slider, with hardly any lag.

 

Disable the red LED on the camera.

When you’re streaming video, you might not want anyone to know when the camera is active. It’s possible to turn off the camera’s red activity LED by doing this:

sudo nano /boot/config.txt

And at the end of the file add the line

disable_camera_led=1

Save and reboot your Pi.

Mounting the twistcam upside down.

The Twistcam is designed to sit on a flat surface the right way up, but if you mount it upside down , hanging from a ceiling or shelf then the video will be upside down and the pan controls the wrong way around. You can fix it by downloading this patch and overwriting the original server.py file.

wget http://www.securipi.co.uk/server.py

 

Start video streaming automatically at boot.

Edit /etc/rc.local so that servod and python3 server.py launch at startup.

nano /etc/rc.local

Insert these lines before the last line which says exit 0

cd /home/pi/twistcam
sudo ./servod
python3 server.py

Save the file and reboot your Pi. Video feed can be controlled from PC or phone.

If you don’t have access to a 3D printer, you can buy the two 3D printed brackets and 8x nylon M2 nuts and bolts here for £11.99 inc VAT.

(Raspberry Pi, Camera and SG90 servo NOT included)

Quantity :

 

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