OBDuino

OBDuino is an open source trip computer design based on the Arduino platform. An OBDuino may be assembled and customised by an electronics hobbyist; it displays information such as instantaneous fuel economy (e.g. miles per gallon, L/100 km or kilometres per litre), engine tuning parameters etc. on an LCD.

OBDuino utilises the On-Board Diagnostics interface found in most modern cars.

OBDuino does not display or reset engine fault codes (which are available over the OBD interface).

The key components of the design are:

Many Arduino-based projects have either custom printed circuit boards available which include the AVR microcontroller (removing the need for an Arduino board), or extension boards that contain the extra circuit and that plug directly into the standard Arduino circuit board. No such PCBs are available for the OBDuino as of September 2009.

The OBDuino project was started in 2008 based on the MPGuino project, with the desire to simplify wiring to the vehicle (i.e. using the standard OBD-II socket rather than directly wiring to the vehicle's fuel injection system and digital vehicle speed sensor) and to access the wide range of engine management data available using OBD.

The main OBDuino thread on the eccomoder forum was started by jmonroe on 1 June 2008 as a fork of MPGuino discussions.

Magister posted an OBDuino announcement to the Arduino forum on 4 December 2008.

As of September 2009, the OBDuino32K code credits these developers:

Main coding/ISO/ELM: Frédéric (aka Magister on ecomodder.com)
LCD part: Dave (aka dcb on ecomodder.com), optimized by Frédéric
ISO Communication Protocol: Russ, Antony, Mike
Features: Mike, Antony
Bugs & Fixes: Antony, Frédéric, Mike

The 32K in the obduino32K name differentiates the code targeted at the Atmega328 with 32k flash memory (i.e. Arduino 2009) version from the Atmega168 16k (Arduino 2008) version.

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