dp100-cli

Command-line tool and Python library for the ALIENTEK DP100 (ATK-MDP100) USB digital power supply. Read live voltage / current / temperature, change setpoints, switch the output, and log samples to CSV — from a terminal or a script.

$ dp100 info
Vout  11.997 V  Iout  0.354 A  P   4.247 W  [CV]  Vin 32.22 V  T 38.2/38.7 C
$ dp100 get
output ON   Vset 12.000 V  Iset 5.000 A  OVP 30.50 V  OCP 5.05 A  (preset 0)

Talks to the device directly over USB HID (via hidapi); no vendor software or driver required.

Install

pipx install dp100-cli && dp100 skill install --global   # CLI + Claude Code skill, one line

pipx keeps the tool isolated and puts dp100 on your PATH (plain pip install dp100-cli works too). The second half is optional: it drops the bundled Claude Code skill into ~/.claude/skills/dp100/ so Claude knows the commands and safety rules in every project; run dp100 skill install (no --global) inside a repo to install it for that project only.

Requires Python 3.9+. hidapi ships binary wheels for CPython 3.9–3.13; on a brand-new interpreter without a wheel, point pipx at an older one, e.g. pipx install --python python3.12 dp100-cli. On Linux add a udev rule so you can open the device without root (see contrib/99-dp100.rules):

sudo cp contrib/99-dp100.rules /etc/udev/rules.d/ && sudo udevadm control --reload-rules

Usage

dp100 info                      # live readings
dp100 get                       # current setpoints
dp100 set --v 12 --i 2.5        # change only the fields you pass (read-merge-write)
dp100 set --ovp 15 --ocp 3      # protection thresholds
dp100 set --v 7.4 --on          # set and enable in one go
dp100 on                        # enable output
dp100 off                       # disable output
dp100 watch --hz 10             # sample continuously, Ctrl-C to stop
dp100 watch --hz 10 --csv --seconds 30 > log.csv
dp100 --json info               # every command can emit JSON
dp100 raw 35 80                 # send a raw function code, print the reply

set refuses a voltage above OVP or a current above OCP instead of tripping the supply's protection. While the output is off the unit reports mode PROT; the CLI shows OFF in that case.

As a library

from dp100 import DP100

with DP100() as psu:
    print(psu.info())                       # dict of live readings
    psu.apply(v=7.4, i=2.0)                 # change setpoints, output state untouched
    psu.output(True)
    print(psu.read_info().power_w)

dp100.protocol (frame building/parsing, CRC, payload dataclasses) has no hardware dependency and can be reused in other transports.

Protocol

Documented in docs/PROTOCOL.md: 64-byte HID reports, [addr, func, seq, len, data…, CRC-16/MODBUS], function 0x30 for live readings and 0x35 to read/write setpoints.

Claude Code skill

A Claude Code skill ships inside the package and in this repo at .claude/skills/dp100/SKILL.md. It teaches Claude the commands, the safety rules (never enables the output unless asked) and the troubleshooting steps.

dp100 skill install            # into ./.claude/skills/dp100/ of the current project
dp100 skill install --global   # into ~/.claude/skills/dp100/ for every project
dp100 skill show               # print it

Platform notes

• Verified on macOS 15 (Apple Silicon) with a real unit.
• Linux and Windows use the same hidapi code path but have not been exercised on hardware yet — reports welcome.
• The DP100 USB-A port does not supply 5 V while the unit is in USB device mode; this tool only uses the USB-C data connection.

Releasing

Bump __version__ in src/dp100/__init__.py, add a CHANGELOG entry, then git tag vX.Y.Z && git push origin vX.Y.Z. The release.yml workflow builds the sdist/wheel and publishes to PyPI via Trusted Publishing (OIDC, no stored token).

Development

git clone https://github.com/AndySze/dp100-cli && cd dp100-cli
python -m venv .venv && .venv/bin/pip install -e '.[dev]'
.venv/bin/pytest            # protocol + CLI tests run without hardware
.venv/bin/ruff check .

Credits

The frame format and function codes were learned by reading the ESP32 host implementation in DP100_ESP32_WebApp (GPL-3.0), which in turn builds on DP100-WebApp. This project is an independent, from-scratch Python implementation of that wire protocol; no code from either project is included, so it is offered under MIT.

License

MIT — see LICENSE.