View Full Version : [posted] How to Make a USB Laptop Keyboard Controller

11-25-2018, 10:40 PM
I made an “Instructable” and YouTube video that describes how to make a USB controller for a laptop keyboard. I designed a circuit card for a Teensy LC that connects to a keyboard FPC cable with up to 26 pins on a 1mm or 0.8mm pitch. The other side of the board is designed for a Teensy 3.2 to connect to an FPC cable with up to 34 pins. The Teensy is initially loaded with an automated continuity test routine which sends the pin connections over USB to an editor when a key is pressed. Then the Teensy is reprogrammed with a USB keyboard controller routine using the key matrix information obtained from the continuity tester. You can download and configure the TMK keyboard routine or use my Arduino routine based on the PJRC Teensyduino “Micro-Manager” functions. I've tested my code out on a dozen different laptop keyboards including one from a Lenovo ThinkPad T61. This keyboard needed a different circuit board for its special 44 pin connector. I designed two different circuit boards, one for a Teensy 3.2 and another for a Teensy LC. The 5 volt tolerant 3.2 directly drives the PS/2 signals for the trackpoint. I added a reset generator and level translators to the LC board so it can also control the trackpoint.
All of the files are located at my GitHub repository at https://github.com/thedalles77/USB_Laptop_Keyboard_Controller
The Instructable is at https://www.instructables.com/id/How-to-Make-a-USB-Laptop-Keyboard-Controller/

I hope you find this project useful.
Frank Adams

11-26-2018, 01:05 AM
This is a pretty cool and knowledgeable video thanks for sharing it with us.

02-13-2019, 02:42 PM
Update: this was posted to the website some time ago. Here's the link.


09-19-2020, 06:26 AM
New link.