Post by thread:[PICLIST] [PIC] [EE] OBDII interface

I did a quick search on the archives but did not find anything relevant. My question is: Does anyone know where I can find the interface and/or protocall used to communicate with OBD? I would like to be able to read and or write to the OBD using either a PIC or if I have to a PC. I am just trying to work out what is needed to do this. I know there is an $80 book available from SAE to do with OBD, but I dont know what is in the book and I am hopeing there is somthing available on-line. Any help would be greatly appreciated. Regards, Allen Demers -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Hello Allen, Do some searching on the J1850 protocol, I think that will give you the communications basics. OBDI is extremely easy, OBDII is a little more complicated (you probably knew that though). Also, check out these sites: http://www.elmelectronics.com/Products/theHome/theHome.htm#ELM323 http://www.autoshop101.com/ http://www.obdii.com I mess with this stuff all the time. Mind if I ask what your application is? What vehicle are you trying to tap into? HTH, Steve Ruse {Original Message removed}

Hello Allen, Do some searching on the J1850 protocol, I think that will give you the communications basics. OBDI is extremely easy, OBDII is a little more complicated (you probably knew that though). The really hard part is finding data stream format info for your particular vehicle. Also, check out these sites: http://www.elmelectronics.com/Products/theHome/theHome.htm#ELM323 http://www.autoshop101.com/ http://www.obdii.com I mess with this stuff all the time. Mind if I ask what your application is? What vehicle are you trying to tap into? HTH, Steve Ruse {Original Message removed}

Allen, May I ask what what the purpose of the device will be? If it's for your own use, I would definitely go with ELM (see Steve's post). It's basically a 12C509 chip that translates VPW/PWM into ASCII. It does a great job - unless, of course, you have an Asian or European car which uses the ISO standard. Vitaliy {Original Message removed}