Anyone remember the TI-99/4A? We do. Well not anecdotally, but out of our fondness for retro computing.
The TI-99/4A was one of the first home computers (in fact its immediate predecessor, the TI-99/4 was the first 16-bit personal computer), released in 1981. In the style of its later (but more popular) cousin, the Commodore 64, it was self-contained in a single console along with a built-in keyboard. What made the TI-99/4 series extra special was its peripheral expansion system, a collection of different modules that could be stacked to expand the system’s capabilities. As you can see, this could get out of hand pretty quickly…
We decided to resurrect one of these bad boys and make a retro-inspired emulation machine — Raspberry Pi style. To run the system, we used the RetroPie Project. This Raspbian-based distro is a fairly comprehensive emulator environment. It’s relatively easy to setup and quite robust.
One of the main things we wanted to do in this build was to retain the utility of the original built-in keyboard. We used Matthew Epler’s method of doing this. He used a Teensy++ 2.0 microcontroller and wrote some great code for that. We wanted to save a few bucks, so we used the standard Teensy 2.0 and modified his code a little to match the pin outs.
Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, or even use Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for MakeCode, CircuitPython, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.