4x4 Matrix 16 Key Membrane Switch Keypad Keyboard for Arduino/AVR/PIC/ARM New

4x4 Matrix 16 Key Membrane Switch Keypad Keyboard for Arduino/AVR/PIC/ARM New

Using 3x4 matrix keypad with the Raspberry Pi 
Written by Chris Crumpacker
Another module of my alarm interface is done. I picked up a 3x4 matrix keypad but couldn't find any good python code examples for it's use. I was able to find a few examples that lead me down the right path in terms of scanning rows first as inputs and then swaping pins to scan the columns. I wrote two libraries, the first just uses 7 of the Raspberry Pi's GPIO pins then I also wrote one that works for the MCP23008 chip since I'm really in a mode of saving pins when I can :) Then also just wrote a demo script to show calling the libraries and their useHere is the code as it stands now, I have some ideas on how to change it to be better but this is fully working for now.

Python Code for 3×4 Matrix Keypad with Raspberry Pi #piday #raspberrypi @Raspberry_Pi

Also see -  WiringPI

 

 

 

Features:

• Brand new and high quality
• Max circuit rating: DC 35V, 100mA
• Insulation resistance: 100M Ohm, 100V
• Dielectric withstand: 250VRms (50-60Hz, 1 min)
• Contact bounce: <=5ms
• Life expectancy: 1 million closures
• Operating temperature: -40 ~ +80°C
• Operating humidity: 40°C, 90% ~ 95%
• Connector type: 8 pin
• Mount type: self-adhesive
• Total length: 160 mm
• Cable length (inc connector):88mm
• Size: 70 x 77 x 1mm

Package Included:

1 X Matrix 16 Key Membrane