racemier

Hi,

Besides the car tuner I have another self therapy which is building OBD2 interfaces
I have a straight one (what goes in comes out) which I use for uploading SW on my car. This works ok.
But my problem starts with my other interface based on a PIC and looks like a diet version of the one from http://www.obddiagnostics.com/.
Now my confusion is all about the initialization with the ECU. Using the uploading SW it starts with pulling the K-line to ground and waits for reply.
But if I read the ISO-9141 and other documentation I see that you first need to send a 0x33 and wait for response. So here I'm a bit confused. Second is the speed, 0x33 at 5 baud and then switch to 10400 baud, how is this done best with the PIC. The 0x33 on 5 baud is not a problem but the 10400 is a question mark. So does anyone have an idea or an example code maybe for the pic...
thx rogier

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Chairboy

It's variable speed in the initialization? I assumed it was 4800bps constant.

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jcdillin

no he is correct, it's 5 then 10400

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S60 Install

jcdillin

I thought I had some example code hanging around here somewhere, but this and this might help you get started. PM if you have any questions.

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S60 Install

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