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j1939 Source Address (read data sent to another module)

Michael Carlyle 5 years ago in IQANdesign updated by Ulrik Zakariasson (Software development) 5 years ago 3

I am sending a message on PGN 55808 form a different source address than the Iqan module (from 250/0 instead of SA 33 which is the Iqan MD4). When I send the message - the engine sends a response back to SA 250 (0/250 on PGN 55808) which I can see on the bus with IqanAnalyse. If I read this channel (PGN 55808) with the Iqan - the response does not show up. Is there a way I can see the response to SA 250 with the Iqan MD4 set to SA 33?

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PGN 55808 is a PDU1 message, and this can appear a bit confusing in IQANdesign.

In IQANdesign 1-3, the PGN property on the JFIN always represents the to bytes PF and PS in the identifier.

This is perfect for J1939 PDU2 messages, since there the PGN is matching these two bytes exactly.


For PDU1 messages, the easiest way to configure reading of a PDU1 message in IQANdesign 3 is by first entering the PGN (e.g. 55808), and then bringing up the dialogue box that lets you enter PF and PS separately.


Then change the PS to the Desitination address, in this case 250:


The property "PGN" will now be changed to 218*256+250=56058, and the identifier will now match what is sent on the bus. With the JFIN assigned to your engine module (address 0), the IQAN master will now check for an identifier where the last three bytes are set to 0xDAFA00


I hope that we will be able to make a more intuitive way of setting this up in version 4.