# KnightOS/KnightOS

OS for z80 calculators

Repository: https://github.com/KnightOS/KnightOS
Canonical: https://ross.abutalabs.com/products/knightos
Language: Assembly
License: NOASSERTION
License Family: other
Topics: knightos, calculator, assembly, custom-kernel, operating-system, z80
Last push: 2021-05-02T06:26:08+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 5096, "days_push": 1949, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1316, forks 181 (observed 2026-08-28T04:04:20.829786+00:00)

## What it is
KnightOS is a third-party Unix-like operating system for TI z80-based graphing calculators, built on a custom kernel with an official userspace that ties together packages, settings, and upgrade files. This repository orchestrates the build of complete ROM and upgrade images for supported TI-73/83+/84+ calculator models using the KnightOS SDK.

## Use cases
- install a custom operating system on a TI-84+ calculator
- build a Unix-like OS image for a z80 calculator
- run a third-party OS on a TI-83 Plus in an emulator
- create an upgrade file to flash onto a TI calculator
- develop against a custom kernel for z80 calculators
- replace the stock TI-OS with an open-source alternative

## When to choose
- you own a supported TI z80 calculator (TI-73, TI-83+, TI-84+ family) and want a Unix-like alternative OS
- you want to tinker with operating system development on constrained z80 hardware
- you want to build custom ROM or upgrade images from source with the KnightOS SDK

## When to avoid
- you need a modern, actively developed OS - the latest release dates to 2021 and development is largely dormant
- you have a calculator outside the supported TI z80 models, such as TI-Nspire or TI-89
- you just want calculator programs or games that run under the stock TI-OS

## Facets
- artifact type: application
- maturity: maintenance
- function: embedded, developer-tools
- domain: operating-systems, embedded-systems, education
- platform: embedded, cross-platform
- tags: z80, ti-calculator, unix-like, custom-kernel, assembly, userspace, rom

## Member repositories
- KnightOS/KnightOS (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:20.829786+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T04:48:23.112096+00:00, confidence not recorded.
  - readme: https://github.com/KnightOS/KnightOS (fetched 2026-08-28T04:04:20.829786+00:00, sha dd747383d02e)
- Data as of 2026-08-30T08:39:29.467469+00:00.