This is an open source adapter which allows using a USB keyboard (and mouse) with a computer that has a PS/2 port. It is shipped in a ready-to-use state. If you want to save some money and are comfortable with electronics such as the Raspberry Pi Pico, you may want to check out the listing for the hat only.

But why?

You may be wondering, but why would anyone want to use this when they could just plug their keyboard and mouse in directly via USB? Great question! The main use is for a security improvement with Qubes OS. There is a discussion about this on their community forum. The other use would be to get a modern (i.e. USB) keyboard to work with an old computer. If you're not into retro computing, this is probably not of interest, but some people might find it to be wonderful.

For comparison, the commercial versions of this device made which cost $80 and they're not open source!

What makes this special?

This product is entirely open source. You can download the designs and, provided you have the right equipment and skills, make one of these yourself. Others can freely make improvements to the product. You can see how its made, which is highly desirable for any security device.

What is included?

This listing is for a complete, usable adapter. It includes:

• one fully assembled hat (the purple board in the photos)
• a Raspberry Pi Pico
• the case (color will vary based on what I have on hand, reach out to me if you want a specific color)
• a PS/2 cable
• a USB-micro to USB-A (female) adapter

It's already flashed with the code to make it work so you can plug in a keyboard to the USB port, the PS/2 cable into your computer and you're all set! And if you want to re-flash the device, the code and instructions for doing this are available here.

If you want to plug in a USB mouse and keyboard, you will need a USB hub. Any USB hub should work just fine, but see the caveats below about motherboard limitations and non-standard mice. If your computer has separate PS/2 ports for a keyboard and mouse, you'll need a splitter to split out this combo cable to individual PS/2 ports. You'll want a Y adapter with 1 socket (female end) and two plugs (male ends).

Caveats

These are all limitations, mostly involving mice. If you're just using this device for a keyboard, you should be good to go.

The firmware for Raspberry Pi Pico supports most mice. Some operate in weird modes and are not fully functional. For details about which mice are or aren't supported, checkout the issue tracker for the firmware. I am not the developer of the firmware, but if you work with the developer to get your mouse supported, I can assure you that my hardware will not limit you.

Some motherboards have a single PS/2 port which supports a keyboard AND a mouse. If that's what you have, this adapter will work fine. However, if you have a motherboard whose combo port supports a keyboard OR a mouse, this PS/2 adapter can't make up for that. Sadly, this seems to be more common than one might expect. My solution to this is to use the PS2 adapter for the keyboard and plug in the mouse to the USB port. If you are really set on using PS/2 for both, you'll need to install an expansion card that gives you another PS/2 port.