I built an open-source kernel for Texas Instruments calculators

In plain words

An open-source kernel designed for Texas Instruments calculators, written entirely in z80 assembly. It provides preemptive multitasking, dynamic memory management, and a Unix-like filesystem for vintage calculators. The project targets developers and enthusiasts interested in low-level programming and retro computing. Contributors can collaborate through the project's IRC channel and GitHub repository.

written from the facts on this page · September 2026

From the sources

In the maker’s words, at launch

You know that old TI calculator you used in high school, then put in a box and forgot about? Have you ever wished you had an operating system for your calculator with preemptive multitasking, dynamic memory management, a tree filesystem conforming to the FHS, and all the comforts of Unix? Well, good news: that's…

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  I'm 17 and I created a Forth interpreter for the TI-84+ calculator2018 · ▲56

  https://github.com/siraben/ti84-forth Hi HN! For the past year I've been getting into programming in Z80 assembly (especially for the TI-84+). More recently I've been learning about the Forth programming language and after a lot of searching online (in vain) for a Forth interpreter for the TI-84, I decided to write one myself. It's been fun demoing this to others, because it's a very unexpected use of a calculator. It's my largest project to date, and I'm interested to know what the HN community thinks, please feel free to critique my code! -- Ben

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