Kegboard Overview

This page describes Kegboard, the Arduino-based controller board for Kegbot.

What is a Kegboard?

Kegboard is the name we use for the microcontroller board used in a Kegbot system. Kegboard is the device that monitors all sensors, including the flow sensors that are essential in any Kegbot configuration.

There are two commonly-used Kegboard targets:

The Kegboard software package includes firmware and support libraries that work with either kind of Kegboard.


Since not all Kegbots are alike, the Kegbot firmware is designed with flexibility in mind: We try to support many features and add-on devices in the core firmware, while still keeping basic functionality tight and fast for the common configurations.

Depending on hardware, the Kegboard firmware can support the following features:

  • Flow Sensing: Two independent flow meter inputs (or 6 on Arduino Mega), allowing you to monitor that many individual beer taps with just one board.

  • Temperature Sensing: Dedicated OneWire bus for reading DS1820 (DS18S20 and DS18B20) temperature sensors. An unlimited number of sensors can be connected, allowing you to independently track keg temperature and ambient temperature.

  • RFID Authentication: Authenticate users with cheap 125kHz RFIDs by connecting the optional ID-12 RFID reader.

  • OneWire Authentication: Authenticate users with durable iButtons.

  • Relay/Value Control: Four general purpose outputs can be used to toggle external devices, such as a valve to prevent unauthorized access. Relays are monitored by an internal watchdog.

  • Buzzer: Kegboard will play a short melody whenever an authentication token is connected or swiped.

  • Extensible Serial Protocol: If you don’t want to use the rest of the Kegbot software, you can still use Kegboard by implementing its simple and extensible serial protocol in your system. (See Kegboard Serial Protocol Reference).


Because of its limited size, certain features (such as relay control and RFID reading) are not available on Kegboard Pro Mini.

Kegboard’s firmware is designed to operate correctly even when a feature is not being used. For example, if the temperature sensor input is not connected, other features will continue to operate normally.