This NumWorks Graphing Calculator Mod Adds a Raspberry Pi as an App

If you’ve taken any high school or college math classes in the last 20 years, there is a very good chance you’ve used the ubiquitous TI-83 or TI-89 graphing calculators. Aside from the obvious graphing functions, they could also be used to code and execute programs. But, those a getting a bit long in the tooth, and NumWorks is the new kid on the block with a lot more to offer.

The NumWorks graphing calculator has a full-color screen, rechargeable battery, a number of applications, and costs just $99. That is about the same as a new TI-83—which has been around for more than two decades. The NumWorks calculator is already awesome how it is, but Zardam has made it infinitely more so by adding a Raspberry Pi Zero W inside the case.

If you’re a regular reader of Hackster and keep up with these kinds of projects, you’re probably assuming Zardam just replaced the NumWork’s electronics with the Pi. But, the actual build is far more clever than that. The Raspberry Pi resides inside the case along with the original electronics, and all of the NumWork’s stock functionality is retained. Zardam just needs to launch the corresponding application the calculator to boot up the Pi and start using it.

That remarkable feat is possible because the NumWorks calculator features an SPI connection for the display. It took a lot of tweaking on the Raspberry Pi, but Zardam was able to use that to output the Pi’s video to the calculator’s screen on demand. The keys are also completely functional, and can be used for typing text and for cursor control on the Pi. The Pi fits nicely inside of the NumWorks case without modification, so the calculator looks completely normal until the Raspberry Pi application is launched.