# Time-Appliances-Project/Time-Card

Develop an end-to-end hypothetical reference model, network architectures, precision time tools, performance objectives and the methods to distribute, operate, monitor time synchronization within data center and much more...

Repository: https://github.com/Time-Appliances-Project/Time-Card
Canonical: https://ross.abutalabs.com/products/time-card
Language: C
License: NOASSERTION
License Family: other
Topics: time-card, ieee3335, synchronization, ptp, ntp, pcie, ptm
Last push: 2026-08-25T01:32:54+00:00

## Health v2 (maintenance only)
Score: 79/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 40, longevity 100
- inputs: {"age_days": 2239, "days_push": 9, "days_rel": 637, "gap_med": 0, "n_releases_24m": 4}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1480, forks 120 (observed 2026-08-28T04:04:50.767819+00:00)

## What it is
Time Card is an open-source PCIe card design (with schematics, BOM, Gerbers, firmware, and Linux driver code) that serves as a precision time server, combining GNSS reception with a high-stability holdover oscillator such as an OCXO or atomic clock. It is the core of the Open Time Server project and the basis of the IEEE P3335 standard for time card architecture and interfaces.

## Use cases
- build an open source PTP grandmaster time server for a data center
- distribute precise time across a network with GNSS and holdover backup
- add a precision time reference card to a Linux server over PCIe
- fabricate my own time card from Gerber files and BOM
- monitor and operate time synchronization in a data center
- replace closed-source network time appliances with an open design
- implement IEEE 3335 compatible time card hardware

## When to choose
- you need an open, customizable precision time appliance for PTP/NTP networks
- you want GNSS timing with atomic clock or OCXO holdover in a PCIe form factor
- you are building infrastructure aligned with the IEEE P3335 standard
- you want to self-fabricate or source compatible time card hardware

## When to avoid
- you need a plug-and-play commercial NTP appliance with vendor support
- your platform is not Linux or lacks a free PCIe slot
- you only need software time sync without dedicated hardware
- you cannot handle hardware assembly or sourcing of GNSS modules and oscillators

## Facets
- artifact type: application
- maturity: active
- function: monitoring, networking, embedded, developer-tools
- domain: hardware, networking, infrastructure-as-code, self-hosted, developer-tools
- platform: self-hosted
- tags: time-synchronization, ptp, ntp, gnss, pcie-card, open-hardware, ieee-3335, precision-time, holdover-oscillator, open-time-server, linux, hardware

## Member repositories
- Time-Appliances-Project/Time-Card (main) score 79

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:50.767819+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 2026-08-30T04:34:13.452135+00:00, confidence not recorded.
  - readme: https://github.com/Time-Appliances-Project/Time-Card (fetched 2026-08-28T04:04:50.767819+00:00, sha 3795ebbb0e44)
- Data as of 2026-08-30T08:39:29.467469+00:00.