CAN Module read vehicle RPM with ECU toolkit

[sfrosty]

Is it possible to read a vehicle's RPM values using a NI-9862 cDAQ CAN Module with the ECU Measurement Toolkit?

[JefeL]

Yes it is possible but with caveats. You would need the A2L descriptor file from the ECU manufacturer and some low level knowledge of the vehicle design. Engineers typically use ECUMC to do low level testing and programming of the ECU directly and not in-vehicle.

Diagnostic information such as RPM values are easily retrieved from production vehicles using one of the standardized diagnostic protocols with the Automotive Diagnostic Command Set (ADCS) instead of using ECUMC.

[sfrosty]

Thank You!

I chose rpm or engine speed to be sure of its' availability, there are numerous parameters I need to access that are only available from the ECU. Can someone direct me to a department within an automotive company that would be able to provide me with the parameters I have listed below. Our Engine calibration department doesn't appear to have this lower level information.

CRO ID CAN identifier of the Command Receive Object (CRO) (example:119d)

Data Transfer Object A message sent from the slave device to the master device (Command
Return Message, Event Message, or Data Acquisition Message).

DTO ID CAN identifier of the DTO. (example:23d)

Station Address (example:81d)
A property which specifies an address to generate a logical point-to-point
connection with a selected slave station for the master-slave command
protocol. One ECU may support several station addresses

SeedKey DLL
A Dynamic Link Library that implements a function to calculate a key to a
given seed to unlock access to ECU resources.

[Hooovahh · Accepted solution]

Who makes your ECU?  They likely won't share this information with you but you can talk to them.   The Seed/Key is probably the thing most protected, but a large majority of the parameters can be read (and a couple written) without it.  Find the group that write the software for your ECU and they will have the information you need.  They just likely won't share it.  These parameters are extremely hardware specific, and there is no one answer.  You will want to find a one or more of these files .DBC, .CDD, .A2L, or .ELF, which describe how to talk to the ECU using various protocols. 

[Minions]

Additionally, you will need to know if the information is being presented as Big or little endian.  Do you happen to know the Baud rate and BTR values?  All of this information should be present within the file extensions that Hooovahh mentioned.  Also, a .MAP file might also be benefit.