This small device can test thousands of old PS/2 keyboards

This small device can test thousands of old PS/2 keyboards

Arduino Team — July 12, 2022

Some vintage computer keyboards, especially units like the IBM Model M, are still quite desirable. Usually, they are popular among mechanical keyboard or retro computing enthusiasts who want period-appropriate hardware. YouTuber Midwest Cyberpunk had thousands of these old keyboards and needed a way to test them. So he built this little Arduino-based device that displays text input from PS/2 keyboards.

IBM developed the PS/2 port standard in the 1980s for the IBM Personal System/2 series of computers. In the 90s, this was the standard for connecting keyboards and mice to PCs. USB made the PS/2 port nearly obsolete in the 2000s, which means there aren't many modern computers that still have PS/2 ports. Midwest Cyberkpunk could have used a vintage computer to test their keyboards, but wanted a more portable option. This PS/2 keyboard tester is easy to carry and provides instant results.

Inside the custom 3D printed case is an Arduino Nano, homemade breakout board, LiPo battery charger and booster board, and a 16 inch backlit LCD display. × 2 characters. The Arduino sketch uses a PS/2 library that can read character hex codes from standard keyboards. Once turned on, Midwest Cyberpunk can simply plug the keyboard into the device. Any key he presses on the keyboard will show on the LCD, so he can quickly press each key to make sure they all work. It's an efficient and affordable way to test large quantities of vintage keyboards in a short time.