SparkFun OBD-II UART

The SparkFun OBD-II UART is a versatile board that provides a serial interface using the ELM327 command set. It allows you to interact with your car's OBD-II bus and supports all major OBD-II standards such as CAN and JBUS. The board is designed with a footprint that directly mates with SparkFun's FTDI Basic. It also features a DB9 connector that pairs with SparkFun's DB9 to OBD-II cable.

The OBD-II (On-Board Diagnostics, Second Generation) is a set of standards that were first introduced in the United States in 1994 to control vehicle emissions. These standards have since been adopted by other countries including Canada, Japan, Australia, and parts of the European Union. OBD-II requires that each compliant vehicle be equipped with a standard diagnostic connector (DLC) and a standard way of communicating with the vehicle’s ECU (Electronic Control Unit). By tapping into the OBD bus, you can access a wealth of information including the status of the malfunction indicator light (MIL), diagnostic trouble codes (DTCs), inspection and maintenance (I/M) information, freeze frames, VIN, and hundreds of real-time parameters.

The SparkFun OBD-II UART board uses the STN1110, an OBD to UART interpreter that can convert messages between any of the OBD-II protocols currently in use, and UART. This 16-bit processor core offers more features and better performance than any other ELM327 compatible IC. It is fully compatible with the ELM327 AT command set and has an extended ST command set. It supports all legislated OBD II protocols including ISO 15765-4 (CAN), ISO 14230-4 (Keyword Protocol 2000), ISO 9141-2 (Asian, European, Chrysler vehicles), SAE J1850 VPW (GM vehicles), SAE J1850 PWM (Ford vehicles), and non-legislated OBD protocols such as ISO 15765 and ISO 11898 (raw CAN). It also supports the SAE J1939 OBD protocol.

Additional features of the SparkFun OBD-II UART board include a UART interface with baud rates from 38 bps to 10 Mbps, a secure bootloader for easy firmware updates, superior automatic protocol detection algorithm, large memory buffer, and voltage input for battery monitoring.