Miscommunication master / slave ECU National Instrument 3C/3D USB-8476

[Marisol8572]

Hello community,

Good day,

Currently I try to send one frame but the slave doesn't respond, I think is a kind of miscommunication, do you know what is happening?

[Bob_Schor]

Ah, a picture of a Front Panel.  It tells us the name (and we can guess at the type) of Controls and Indicators that "do all the work on the Block Diagram", but no Block Diagram.  In addition to a (relatively useless) "picture" of the Block Diagram, we are best served by your attaching the actual VI (hint -- a file with the extension .vi), and, if necessary, saving it for a version no later than LabVIEW 2021.

I, for one, don't even understand the title of this Post.  What is "ECU"?  What is "3C/3D"?  I can look up USB-8476, but I don't know what a LIN Network is.  A little more information from you will help us to help you.

Bob Schor

[ZYOng]

This question is best to be posted on the  Automotive and Embedded Networks board.

I work primarily on NI-XNET and have very little experience with NI-CAN so I can't comment much. However, I noticed that the termination property is not enabled. Is the LIN cable terminated? Are you able to do communication using other ID other than the master request frame of 0x3C for diagnostic?

[Marisol8572]

Hello ZYOng, 

Thank you very much for your response and orientation,

Yes the LIN Cable is finished, but unfortunately the slave doesn't response to another frame for diagnostic.

[rolfk]

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@Marisol8572 wrote:

Hello ZYOng, 

Thank you very much for your response and orientation,

Yes the LIN Cable is finished, but unfortunately the slave doesn't response to another frame for diagnostic.

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Hmm, when ZYOng asked about if the cable was terminated he didn't mean if you have finished the cable, but if it has a proper impedance termination. LIN has an active driven state and a passive held state. Without a proper termination with resistors the bus may be floating in the passive state and not result in a valid signal level.

[Marisol8572]

Hello Rolf,

Thank you for the orientation, is my first time working with LIN-BUS so I'm learning. 

Yes the cable is terminated, currently I could run the program and have response from the frame for diagnostic, but only with one slave, the other slave has the next Log Bus Error: 

84 00 01 06 00 00 3D (The LIN interface slave task received a header but no response). Page. 11-90 NI-CAN Hardware and Software Manual