Tag Archives: keypad

In this lesson we add an audible alarm to our security system. I am connecting to a Bluetooth speaker, and then using the pygame library to play an alarm sound. The pygame library will play any .mp3 file, so search the internet and find a suitable alarm sound for your system. I amusing an air raid siren, and really like it! Below for your convenience is the code we develop in this video:

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BOARD)
PIRpin=12
GPIO.setup(PIRpin,GPIO.IN)
import LCD1602
import KPLIB
from time import sleep
import threading
myPad=KPLIB.keypad(retChar='D')
LCD1602.init(0x27,1)
myString=''
pwd='1234'

from pygame import mixer
mixer.init()
mixer.music.load('alarm.mp3')

def readKP():
    global myString
    while myString != '*':
        myString=myPad.readKeypad()
        sleep(.5)
readThread=threading.Thread(target=readKP,)
readThread.daemon=True
readThread.start()
while myString != '*':
    CMD=myString
    if CMD=='A'+pwd:
        LCD1602.write(0,0,'Armed          ')
        moveVal=GPIO.input(PIRpin)
        if moveVal==1:
            LCD1602.write(0,1,'Intruder Alert')
            mixer.music.play()
            sleep(10)
        if moveVal==0:
            LCD1602.write(0,1,'All Clear      ')
    if CMD=='B'+pwd:
        LCD1602.write(0,0,'UnArmed        ')
        LCD1602.write(0,1,'               ')
    if CMD=='C'+pwd:
        LCD1602.write(0,0,'Password?      ')
        LCD1602.write(0,1,'               ')
        while myString=='C'+pwd:
            pass
        pwd=myString
        LCD1602.write(0,0,pwd+'         ')
        sleep(2)
        LCD1602.write(0,0,'               ')
        LCD1602.clear()
sleep(1)
GPIO.cleanup()
LCD1602.clear()
print('GPIO Good to Go')

import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BOARD)

PIRpin=12

GPIO.setup(PIRpin,GPIO.IN)

import LCD1602

import KPLIB

from time import sleep

import threading

myPad=KPLIB.keypad(retChar='D')

LCD1602.init(0x27,1)

myString=''

pwd='1234'

from pygame import mixer

mixer.init()

mixer.music.load('alarm.mp3')

def readKP():

global myString

while myString != '*':

myString=myPad.readKeypad()

sleep(.5)

readThread=threading.Thread(target=readKP,)

readThread.daemon=True

readThread.start()

while myString != '*':

CMD=myString

if CMD=='A'+pwd:

LCD1602.write(0,0,'Armed ')

moveVal=GPIO.input(PIRpin)

if moveVal==1:

LCD1602.write(0,1,'Intruder Alert')

mixer.music.play()

sleep(10)

if moveVal==0:

LCD1602.write(0,1,'All Clear ')

if CMD=='B'+pwd:

LCD1602.write(0,0,'UnArmed ')

LCD1602.write(0,1,' ')

if CMD=='C'+pwd:

LCD1602.write(0,0,'Password? ')

LCD1602.write(0,1,' ')

while myString=='C'+pwd:

pass

pwd=myString

LCD1602.write(0,0,pwd+' ')

sleep(2)

LCD1602.write(0,0,' ')

LCD1602.clear()

sleep(1)

GPIO.cleanup()

LCD1602.clear()

print('GPIO Good to Go')

Raspberry Pi

Raspberry Pi LESSON 36: Motion Detection Alarm System With LCD and Keypad

November 10, 2022 admin

In this lesson we show the basic framework for an Alarm System with operator control through a keypad, and output to an LCD screen. We incorporate a PIR sensor to detect motion. In the next lesson we will add an audible alarm. For your convenience, the code developed in the above video is included below:

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BOARD)
PIRpin=12
GPIO.setup(PIRpin,GPIO.IN)
import LCD1602
import KPLIB
from time import sleep
import threading
myPad=KPLIB.keypad(retChar='D')
LCD1602.init(0x27,1)
myString=''
pwd='1234'
def readKP():
    global myString
    while myString != '*':
        myString=myPad.readKeypad()
        sleep(.5)
readThread=threading.Thread(target=readKP,)
readThread.daemon=True
readThread.start()
while myString != '*':
    CMD=myString
    if CMD=='A'+pwd:
        LCD1602.write(0,0,'Armed          ')
        moveVal=GPIO.input(PIRpin)
        if moveVal==1:
            LCD1602.write(0,1,'Intruder Alert')
        if moveVal==0:
            LCD1602.write(0,1,'All Clear      ')
    if CMD=='B'+pwd:
        LCD1602.write(0,0,'UnArmed        ')
        LCD1602.write(0,1,'               ')
    if CMD=='C'+pwd:
        LCD1602.write(0,0,'Password?      ')
        LCD1602.write(0,1,'               ')
        while myString=='C'+pwd:
            pass
        pwd=myString
        LCD1602.write(0,0,pwd+'         ')
        sleep(2)
        LCD1602.write(0,0,'               ')
        LCD1602.clear()
sleep(1)
GPIO.cleanup()
LCD1602.clear()
print('GPIO Good to Go')

import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BOARD)

PIRpin=12

GPIO.setup(PIRpin,GPIO.IN)

import LCD1602

import KPLIB

from time import sleep

import threading

myPad=KPLIB.keypad(retChar='D')

LCD1602.init(0x27,1)

myString=''

pwd='1234'

def readKP():

global myString

while myString != '*':

myString=myPad.readKeypad()

sleep(.5)

readThread=threading.Thread(target=readKP,)

readThread.daemon=True

readThread.start()

while myString != '*':

CMD=myString

if CMD=='A'+pwd:

LCD1602.write(0,0,'Armed ')

moveVal=GPIO.input(PIRpin)

if moveVal==1:

LCD1602.write(0,1,'Intruder Alert')

if moveVal==0:

LCD1602.write(0,1,'All Clear ')

if CMD=='B'+pwd:

LCD1602.write(0,0,'UnArmed ')

LCD1602.write(0,1,' ')

if CMD=='C'+pwd:

LCD1602.write(0,0,'Password? ')

LCD1602.write(0,1,' ')

while myString=='C'+pwd:

pass

pwd=myString

LCD1602.write(0,0,pwd+' ')

sleep(2)

LCD1602.write(0,0,' ')

LCD1602.clear()

sleep(1)

GPIO.cleanup()

LCD1602.clear()

print('GPIO Good to Go')

Python, Raspberry Pi

Library for Reading a 16 Button Keypad on the Raspberry Pi

October 27, 2022 admin

In this lesson we show you how to create a Python Class and Library that allows you to easily get user input on a Raspberry Pi from a 16 button keypad. This will allow very easy interaction with the keypad.

The Library Code which we develop in the video is presented below for your convenience:

class keypad:
    def __init__(self,rows=[11,13,15,29],columns=[31,33,35,37],keyLabels=[['1','2','3','A'],['4','5','6','B'],['7','8','9','C'],['*','0','#','D']],retChar='D'):
        import RPi.GPIO as GPIO
        self.rows=rows
        self.columns=columns
        self.retChar=retChar
        self.keyLabels=keyLabels
        GPIO.setmode(GPIO.BOARD)
        for i in rows:
            GPIO.setup(i,GPIO.OUT)
        for j in columns:
            GPIO.setup(j,GPIO.IN,pull_up_down=GPIO.PUD_DOWN)
    def readKeypad(self):
        from time import sleep
        import RPi.GPIO as GPIO
        keyStrokes=''
        noPress=True
        noPressOld=True
        while True:
            noPress=True
            for myRow in [0,1,2,3]:
                for myColumn in [0,1,2,3]:
                    GPIO.output(self.rows[myRow],GPIO.HIGH)
                    butVal=GPIO.input(self.columns[myColumn])
                    GPIO.output(self.rows[myRow],GPIO.LOW)
                    if butVal==1:
                        myChar=self.keyLabels[myRow][myColumn]
                        if myChar==self.retChar:
                            return keyStrokes
                        noPress=False
                    if butVal==1 and noPressOld==True and noPress==False:
                        keyStrokes=keyStrokes+myChar
            noPressOld=noPress
            sleep(.25)

class keypad:

def __init__(self,rows=[11,13,15,29],columns=[31,33,35,37],keyLabels=[['1','2','3','A'],['4','5','6','B'],['7','8','9','C'],['*','0','#','D']],retChar='D'):

import RPi.GPIO as GPIO

self.rows=rows

self.columns=columns

self.retChar=retChar

self.keyLabels=keyLabels

GPIO.setmode(GPIO.BOARD)

for i in rows:

GPIO.setup(i,GPIO.OUT)

for j in columns:

GPIO.setup(j,GPIO.IN,pull_up_down=GPIO.PUD_DOWN)

def readKeypad(self):

from time import sleep

import RPi.GPIO as GPIO

keyStrokes=''

noPress=True

noPressOld=True

while True:

noPress=True

for myRow in [0,1,2,3]:

for myColumn in [0,1,2,3]:

GPIO.output(self.rows[myRow],GPIO.HIGH)

butVal=GPIO.input(self.columns[myColumn])

GPIO.output(self.rows[myRow],GPIO.LOW)

if butVal==1:

myChar=self.keyLabels[myRow][myColumn]

if myChar==self.retChar:

return keyStrokes

noPress=False

if butVal==1 and noPressOld==True and noPress==False:

keyStrokes=keyStrokes+myChar

noPressOld=noPress

sleep(.25)

To use this code as a library, save it in the same folder as your python programs, and save it as KPLIB.py

import RPi.GPIO as GPIO
from KPLIB import keypad
myPad=keypad(retChar='A')
myString=myPad.readKeypad()
print(myString)
GPIO.cleanup()

import RPi.GPIO as GPIO

from KPLIB import keypad

myPad=keypad(retChar='A')

myString=myPad.readKeypad()

print(myString)

GPIO.cleanup()

This is a simple demo program that calls the library above, to receive input from the keypad.

Technology Tutorials

Tag Archives: keypad

Raspberry Pi LESSON 37: Raspberry Pi Security System

Raspberry Pi LESSON 36: Motion Detection Alarm System With LCD and Keypad

Library for Reading a 16 Button Keypad on the Raspberry Pi

Making The World a Better Place One High Tech Project at a Time. Enjoy!