5 Baud startup sequence

Hi,

I have looked at the startup sequence used by OBDTool and VAG-Com.

The K line voltage as a function of time for

OBDTool (after pressing the 'Start Communication' button:
--_--__--__--

VAG-Com:
Depending on the module selected, the sequence seems to be
the module number (as it appears on the button) as 7bit+parity. e.g.
--_-_______-- Engine 0x01
--__-______-- Trans. 0x02
--_--_____--- Brake 0x03
--_-_-_-___-- Airbag 0x15
etc.

I will now get the extension lead, take the scope to the car,
and see what the responses look like... My main question is
whether the interface switches to the 9600 Baud mode straight
away, or is there any further exchange at 5 Baud?

A different question: what is the 'Login' function, which is
available in both OBDTool and VAG-Com? What number is one
supposed to type in to get past the prompt?

Cheers

John

 
Received on Wed Aug 02 10:40:21 2000