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randogoth de4ca8fdb6 docs: add AI declaration and badges
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STRIX

Satellite True Random Information eXtractor

Arduino MKR Vidor 4000 Built with Devbox License: Apache 2.0 AI-DECLARATION: copilot

A portable wireless True Random Number Generator built on an Arduino MKR Vidor 4000.

Design

Entropy comes from FPGA ring oscillators whose sampled timing jitter is XOR-combined into output bits, with no pseudo-random post-processing. A SAMD21 serves the results over USB, over HTTP on its own WiFi access point (stationary mode, on a charger), or over Bluetooth LE (mobile mode, on battery).

  • 4 independent generators × 90 ring oscillators. Each generator XORs its rings every 120 MHz clock (spatial) and then several consecutive bits (temporal, default 5): about 24 Mbps per generator.
  • Separate stream per generator, plus a combined stream of all healthy generators
  • On-device health tests per generator: NIST SP 800-90B repetition count and adaptive proportion, plus a dead-ring monitor
  • Live statistics per trial: bias, z-score, random walk and lag-1 autocorrelation, with rolling and cumulative windows
  • Configurable random-walk / majority-vote bias amplifier on a bias path and an autocorrelation path, with sub-trial voting
  • Von Neumann extractor that can be toggled on the stream, statistics and amplifier paths
  • Per-second trials in Global Consciousness Project format (200-bit XOR-masked sums per generator, plus full-rate sums), with Stouffer Z and network variance
  • Raw ring captures and frequency measurement for characterization

The USB, HTTP and BLE API is documented in arduino/strix/API.md.

Command-line client

tools/strix.py talks to the device over USB; run it with devbox run strix <command> or uv run tools/strix.py <command>. It finds the board by its USB ID (override with --port or STRIX_PORT).

Command Does
id, health, amp, get Prints the device's reply
stats [--reset] Prints the statistics, or restarts them
set KEY VALUE Changes a setting (keys in the API documentation)
entropy N [--out FILE] N entropy bytes as hex, or binary into a file
watch stats|amp Prints every new trial until Ctrl-C
gcp [--log FILE] [--full] [--seconds N] Follows the per-second GCP-format trials
send LINE Sends any command line and prints the reply

gcp prints one line per second: UTC time, second number, the four 200-bit sums, Stouffer Z, Z², and the cumulative Z² − 1 with its p = 0.05 envelope (* when outside). --full tracks the full-rate trials instead. It reconnects after USB dropouts and fills missed seconds from the device's 60-second history. --log appends GCP-style CSV rows, 13,<unix time>,<UTC date-time>,<g0>,<g1>,<g2>,<g3> (empty for unhealthy generators), after a 12,gmtime,Date/Time,g0,g1,g2,g3 header.

TODO

  • WiFi credentials stored on the device instead of compile-time defaults
  • Battery pack
  • 3D case

Development Notes