I apologize for the troubles - I did add the pinout for this product, as a picture. Unfortunately, only the first three pictures appeared on this page. Please take a look at the second picture for the pinout. Thank you for your understanding.

This was designed for building, and experimenting with, retro computing projects. With the old computers, they were often programmed in hexadecimal, and the 10-key telephone-style keypads did not fit the bill. In addition, when I was able to find 16-key keypads, the numbering was designed along the lines of the telephone-style keypad, and was not fit for quick hexadecimal data entry.

This keypad kit will enable you to plug a hexadecimal keypad directly into your breadboard. This will quickly allow you to design user input into your project. As a hexadecimal keypad, this is a perfect fit for entering hex data directly into a microcontroller, or a classic computer. The keypad is arranged in an X-Y matrix with the rows and columns brought out to the nine pins at the top of the keypad.

Following the table below, and the diagram picture, when the “5” key is pressed, it would short together pin 4 and pin 7 on the 9-pin connector. The remaining pins are left unconnected. By having your computer scan the columns by placing a high on each column, one by one, and then reading the row pins, your system can tell which key is pressed. You would also need to account for keybounce with a short delay/retest subroutine.

This is how the pins are wired:

• Pin 1 (the left-most pin) is ground
• Pin 2 is connected to the bottom row
• Pin 3 is connected to the next row up
• Pin 4 is connected to the second-from-the-top row
• Pin 5 is connected to the top row
• Pin 6 is connected to the left-most column
• Pin 7 is connected to the next column to the right
• Pin 8 is connected to the second-from-the-right column
• Pin 9 is connected to the right-most column

See the second picture for a schematic of these connections.