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Topic: OBDuino & OBDuinoInterface (Read 5272 times) previous topic - next topic

OBDuino & OBDuinoInterface


The OBDuino is an in-car real-time display of various information, like speed, RPM, instant fuel consumption or average trip fuel consumption as well as others PIDs supported by the car.


... It is based on an Atmel AVR ATMEGA168P chip that contains 16K of flash, 1K of RAM and 512bytes of EEPROM, an LCD display, 3 buttons, a few $ of electronics components.

The OBDuino connects to the car on its OBD-II plug ... A lot of signals are on this plug as well as battery voltage and ground. Using a standard OBD-II to DB9F cable brings us what we need.

The interface to the car is made with either a Freescale MC33290 for ISO only, a Microchip 2515 for CAN only, or an ELM327 (a third-party pre-programmed PIC) that talks PWM/VPW/ISO/CAN ...


You cannot directly connect pins from the OBD-II plug to the Arduino board. You need a small interface that convert the signal ...

For all cases: The Arduino is powered by the 12V line coming from the cable too so you need to bring some wires from the DB9M to the Arduino like this:

Arduino 12V input ------------------ DB9M pin 9 (12V Battery)
Arduino GND input ------------------ DB9M pin 2 (Chassis Ground)

ISO Interface

Re: OBDuino & OBDuinoInterface

Reply #1
Have you played around with it any?  It definitely sparked some interest from me.  Now to only get time i can actually sit down and play with all my tech gadgets... real life getting in the way :)

Re: OBDuino & OBDuinoInterface

Reply #2
Just saw it, and realized there wasn't a OBD-oriented Arduino project in the forum.