WHILL Serial API — Model CR2

Two-wheel drive with a single RS232C interface. The tester and emulator below talk to the WHILL directly from your browser over the Web Serial API — no installation, no driver, no account.

Documentation & Tools

Specification

Frame format, control commands, state data, timing and connector pinout.

Read online Markdown source on GitHub

Tester v1.01

Send commands to a real WHILL and watch the returned state data live. Use it to verify your integration.

Open in browser Download

Emulator v1.01

Emulates a WHILL device: parses host commands and serves Dataset0 / Dataset1. Develop without hardware.

Open in browser Download

Before you use the tools

These notes apply to the Tester and Emulator only. The specification is an ordinary web page — read it in any browser, no setup needed.

Chrome or Edge is required. The tools use the Web Serial API, which Safari and Firefox do not support.
Your data stays on your machine. The tools communicate only between your browser and the WHILL over the serial port. Nothing is sent to any server.
They work offline. Each tool is a single self-contained HTML file — download it and open it from a local disk on an isolated network.

Connection

Applies to	Model CR2, Wheeled Robot Base, Electrical System Kit
Transport	RS232C, 38400 bps, 8-N-2
Connector	D-sub 9-pin
Serial API version	1.1

Using an Omni Platform? Its command set differs — see the product list.