Topic created on: June 24, 2010 17:36 CDT by blckonyxx .


Ok....not tech savvy whatsoever, so please bear with me.

I have an automotive application problem. I have installed a modern transmission installed in a slightly older car and it does not work. I am seeking to create an independent interface module to control an electronically controlled transmission that has its own internal module. Access to a Transmission module is not possible at this time, but can be obtained if necessary.

The nature of the approach to this project is a reverse engineering exercise.

What I know is the follow:

-The Transmission, Engine and Body modules MUST communicate via 2 forms of networks...(A) High Speed LAN and (B) Low Speed LAN.

-The High Speed LAN (A) is a two line parallel architecture having a "lo" and "hi" side. The Engine and Transmission module ONLY communicate with each other on this network.

-The Low Speed LAN (B) uses a 1-wire serial network with varying communication speeds up to approximately 90 kbps. The Engine or Transmission module only communicate with the Bodymodule on this network

-The Body module is the master or "gateway" module between the two LANs.

-The Body module initiates a 'search' or 'wake up' voltage signal along the 1-wire Low Speed LAN (B) to the Transmission, Engine and other modules. Their response confirms their presence and then authorization to proceed operation is given. Without this initial "search/wake up" signal the Transmission module will NOT communicate with the Engine module along the High Speed LAN (A) .

-The Body module maintains a "constant" minimum KBPS communication with the 1-wire Low Speed LAN (B) modules afterwards. Dropping this constant communication will trigger a 'failsafe' response from all modules on this network. The specifics of the failsafe response is unknown and therefore preferred to be avoided in our module's design.

What is needed:

-Isolate the Body module's "initiation" function(s)/program/code/pulse

-Isolate Body module's "maintenance" function(s)/program/code/pulse

-Create an independent module to automatically emulate same functions.

I have more detailed information, including schematics and actual components.

Any ideas????

Jesse