XCP Custom Device calls to ALLOC_DAQ include all mesasurement tasks

[DerekTheRockRockson]

I'm using VeriStand 2017 with ECUMC 18.0 to communicate via XCP with my ECU and I've added a number of measurement tasks to the XCP Custom Device, some tasks using a "Read/Write Mode" of "Polling" and some using the "DAQ List" option. As I added more of these measurement tasks, I noticed that all the measurement tasks with the "DAQ List" mode selected would stop working. Digging through the XCP debug logs the custom device can generate, I noticed the XCP command "ALLOC_DAQ" would get called with an input equal to the TOTAL number of Measurement tasks I had defined, not just the tasks with the "DAQ List" mode selected. The ECU's code had a configured limit on the number of DAQ lists it was willing to support and I had crossed the line well before I was expecting to.

For example, if I had 3 measurement tasks with "Read/Write" mode set to DAQ and 3 with the mode set to "Polling", the "ALLOC_DAQ" message sent by the XCP Custom Device would "ALLOC_DAQ DAQCnt=6".

Is there a deeper reason all measurement tasks are included in this "ALLOC_DAQ" call? With my basic understanding of XCP, I would have expected only the measurement tasks with the "Read/Write Mode" "DAQ List" would to have space allocated.

[Tim_Ew · Accepted solution]

Hi DerekTheRockRockson,

This is indeed a bug in the software. In your example, only 3 DAQ lists should be allocated. Thanks for bringing this to our attention. I filed a bug report and it should be fixed in one of the next versions of ECUMC. 

The bug is that all measurement tasks in the session, whether they are configured as a DAQ list or with polling, are used to request DAQ lists if at least one of them is configured as a DAQ list. Currently, the only way around this is to use only one of them, DAQ lists or polling. I recommend DAQ lists because it requires less traffic to communicate the same information.

Kind Regards,

Tim

[DerekTheRockRockson]

Hello Tim,

Thanks for filing that bug report for me. Its good to know that my intuition is correct. And thanks for the fast reply!

-Derek

[croohcifer]

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@Tim_Ew wrote:

This is indeed a bug in the software. In your example, only 3 DAQ lists should be allocated. Thanks for bringing this to our attention. I filed a bug report and it should be fixed in one of the next versions of ECUMC. 

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Hi Tim,

Could you please provide the CAR number?

Thanks!

David

[croohcifer]

For those interested, this is ECU MC Toolkit CAR 734080.