rpi-hwid — Raspberry Pi hardware identity

What is this Raspberry Pi wearing, what powers it, and what is soldered to it? rpi-hwid answers from the Pi itself, out of evidence the firmware and kernel already expose but nothing collects: HAT ID EEPROMs (including the ones the firmware never reads), the Pi 5's own verdict on its USB-C supply, the PMIC's input and RTC-cell voltages, the fan header, the USB tree, and which network interfaces are soldered down.

Around that probe: separate modules for an FPGA board (NeTV2, Acorn, Arty, Cynthion) or a Tiny Tapeout demo board attached to the Pi; a collector that runs the lot over ssh across a fleet, one JSON document per host; and a label generator that turns those documents into sticker sheets carrying only what cannot change — serial numbers, MAC addresses, Device DNA, an ECP5's TraceID. The same probe runs unchanged on an Orange Pi PC.

The labels

rpi-hwid labels --data DIR --out labels.pdf lays out 63.5 × 38.1 mm labels, 21 to an A4 sheet (the Avery L7160 grid), from a directory of collected documents. Every label carries only what cannot change, and every identifier that might otherwise be typed is also a QR code. Cropped from a rendered sheet:

Pi 5 with a Waveshare PoE M.2 HAT+ (B); the radio is disabled, so no wlan MAC	Pi Zero W with the Waveshare PoE- ETH-USB-HUB-HAT; the bonnet's RTL8152 is its eth MAC	Orange Pi PC; eth MAC derived by U-Boot from the SoC serial, no radio
NeTV2, carrying the Device DNA and the name derived from it	Arty A7-35T, with its Digilent serial and its flash's unique id	An Acorn CLE-215+ under gateware that hides its PCIe id: named by its die
Cynthion r1.4, an ECP5 board, keyed on the die's TraceID; its flash UID sits below
TT06 chip on a TT06+ demo board	TTGF0p2 on a DBv3 board; wafer.space ran it on GlobalFoundries	An FPGA breakout standing in for the ASIC, on the same DBv3 board
ASIX AX88179 USB 3.0 gigabit adapter	Realtek 802.11ac USB WiFi adapter	Linksys USB3GIGV1 USB 3.0 gigabit adapter

Print at 100 % — "fit to page" shrinks the grid and every label lands off its sticker. The layouts band by band, the other options, the derived board names and the artwork are in docs/LABELS.md.

Install

uv tool install 'rpi-hwid[labels]'     # everything, including the label generator
pip install rpi-hwid                   # probe, collector, names: no dependencies at all

Or as a Debian package on Raspberry Pi OS or Debian bookworm, trixie or sid, from the signed apt repository at https://mith.ro/rpi-hwid/ (the page has the three-line setup for each suite):

sudo apt install python3-rpi-hwid      # provides the rpi-hwid command

Nothing needs installing on the Pi being probed. The probe is one dependency-free file that runs on any python3 3.5 or later, so it can be sent over ssh on stdin:

ssh pi@host 'python3 -' < src/rpi_hwid/probe.py
ssh pi@host 'python3 - --json' < src/rpi_hwid/probe.py

On the Pi it wants passwordless sudo for the firmware tools (dtparam and vcgencmd). The 40-pin header is read straight from /dev/i2c-*, so it needs neither sudo nor i2c-tools — only membership of the i2c group. Without any of it the probe still reports what it can.

Quick start

A Pi 5 powered through a PoE splitter, with a USB Ethernet adapter:

$ rpi-hwid probe
Raspberry Pi 5 Model B Rev 1.0  serial d88100008543dc30  rev c04170
  header : nothing identifiable on the header
  signal : USB-C as the firmware sees it: max_current 900 mA, no PD contract; 5 V input 4.83 V
  signal : fan header: disabled
  signal : RTC battery: none (0.00 V)
  signal : power port: throttled=0x0
  power  : external supply on USB-C advertising 900 mA by resistor: a PoE splitter or a USB-A lead
  onboard: eth    2c:cf:67:16:bd:98  macb
  onboard: wlan   2c:cf:67:16:bd:99  brcmfmac
  usb net: 0b95:1790 ASIX Elec. Corp. AX88179  00:0e:c6:82:b5:e1  ethernet

Revision codes decode offline, on any machine:

$ rpi-hwid revision c04170 9000c1 a020d3
c04170: Raspberry Pi 5, 4 GB, Rev 1.0, BCM2712
9000c1: Raspberry Pi Zero W, 512 MB, Rev 1.1, BCM2835
a020d3: Raspberry Pi 3 Model B+, 1 GB, Rev 1.3, BCM2837

The commands

rpi-hwid probe [--json] [--fpga] [--jtag] [--flash] [--tinytapeout]
                                                      on a Pi: what is this?
rpi-hwid fpga [--json] [--jtag] [--flash]             on a Pi: which FPGA board?
rpi-hwid tinytapeout [--json] [--no-repl]             on a Pi: which Tiny Tapeout board?
rpi-hwid collect --out DIR [-J JUMP] [--fpga] [--tinytapeout] HOST…
                                                      over ssh: one JSON per host
rpi-hwid labels --data DIR --out labels.pdf           print-ready labels from that data
rpi-hwid name --netv2 DNA… | --arty SERIAL…           the derived board names
rpi-hwid revision CODE…                               decode Pi revision codes

Reference

• docs/PROBE.md — what each signal proves, how the power verdict is reached, the Orange Pi, and the FPGA and Tiny Tapeout modules.
• docs/COLLECT.md — collecting a fleet over ssh, the JSON document the rest of the package consumes, and reading it from Python.
• docs/LABELS.md — the derived names, the five label layouts, the label options and the artwork.
• docs/DEVELOPING.md — contributor notes.
• RELEASING.md — how a version reaches PyPI and apt.

Development

uv sync --all-extras --group dev
uv run ruff check && uv run mypy && uv run pytest

The rest — the Python 3.5 rule for the probe files, what the tests need installed, regenerating the images, building the Debian package — is in docs/DEVELOPING.md, and how a version reaches PyPI and apt is in RELEASING.md.

Origin

Worked out on a fleet of Pi Zero W, 3B+, 4 and 5 hosts carrying NeTV2, Acorn and Arty boards, powered by a mix of Waveshare PoE HATs and external PoE splitters, plus Orange Pi PCs on the welland.fpgas.online pool, in September 2026. The rules above are what those boards showed; a board that behaves differently is a bug report. The Tiny Tapeout module was written from the SDK's public sources (tt-micropython-firmware, tt-demo-pcb, tt-support-tools) and tested against an emulated board; a report from a real demo board is welcome.