• Description

  Description-

  Punch in your secret key into this numeric matrix keypad. This keypad has 12 buttons, arranged in a telephone-line 3x4 grid. It's made of a thin, flexible membrane material with an adhesive backing (just remove the paper) so you can attach it to nearly anything. The keys are connected into a matrix, so you only need 7 microcontroller pins (3-columns and 4-rows) to scan through the pad. Check the tutorials tab for links to an Arduino library and example code.
  
  We include a 7-pin extra-long header strip so you can plug this into a breadboard with ease.

• Technical Details

  Technical Details+

  • Weight: 7.5 grams
  • Keypad dimensions: 70mm x 77mm x 1mm (2.75" x 3" x 0.035")
  • Length of cable + connector: 85mm
  • 7-pin 0.1" pitch connector

  There is a very nice Matrix Keypad Arduino library that works great with this item. The only thing we suggest is to change the initialization code in the examples to this:

  #include "Arduino.h"
  #include "Keypad.h"
  
  const byte ROWS = 4; //four rows
  const byte COLS = 3; //three columns
  char keys[ROWS][COLS] = {
    {'1','2','3'},
    {'4','5','6'},
    {'7','8','9'},
    {'*','0','#'}
  };
  byte rowPins[ROWS] = {8, 7, 6, 5}; //connect to the row pinouts of the keypad
  byte colPins[COLS] = {4, 3, 2}; //connect to the column pinouts of the keypad
  
  Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );
  

  This will swap the * and # keys and also let you connect to the Arduino to match this image

  

• Learn

  Learn+

  

  Biometric Lock Box

  A triple-security lock box for your most valuable possessions

  

  Collin's Lab: Binary & Hex

  Explore strange new ways to count in code.

  

  Costume Triggers & Actuators

  Interactive Halloween

  

  Matrix Keypad

  Punch up your project with a matrix keypad

  Grand Central Soundboard in Ten Minutes

  With a few parts, you can make a super soundboard with the Adafruit Grand Central

MAY WE ALSO SUGGEST...

Membrane 1x4 Keypad + Extras

Membrane LED Keypad + extras

Mechanical Decade Counters - Large Size - Pack of 5

3x4 Phone-style Matrix Keypad

Mechanical Decade Counters - Small Size - Pack of 5

4x4 Matrix Keypad

3x4 Matrix Keypad