[Allan Schwartz] decided to document his experience using Fritzing to design, fabricate, and test a custom Arduino shield PCB, and his step-by-step documentation makes the workflow very clear.

connect to the column C1-C3 pinouts of the keypad Next is a project example, where the Arduino is instructed to do something based on a correct key (secret number) being entered into the keypad, ...

Watch the video below to learn more about his Arduino-based portable keypad that connects to your Arduino development board and offers the complete alphabet, numbers 0-9 as well as several commands.