XCP DAQ - Timing Source - ECU and CAN Timing with Waveform output

[timtamslam]

ECUMC 18.5 adds Timing Source options for XCP DAQ List, allowing one to use ECU timestamps, which is great!

http://zone.ni.com/reference/en-XX/help/371602T-01/niecumchelp/mcsetpropertyvi/

I want to make sure I am correctly utilizing this feature in my application.

Can anyone explain how the timestamp from the ECU is applied to the DAQ List read when "ECU Timing" source is used with a "Waveform" type DAQ Read?

My assumption is that it functions similar to XNET's Signal Input Waveform Mode. In the ECUMC DAQ List the  XNET hardware is resampling incoming signals at the rate specified in the DAQ List input for "Sample rate". this is setting up our 'dt' in the waveform. Based on the "ECU Timing" description, "Start Time is taken from the host" and "increments are taken from the ECU",

So the host sets our 't0' and the values that correspond with each 'dt' step in the waveform are resampled based on the timestamp value provided by the ECU and NOT by the time in which the XNET HW buffered/stamped the value. 

Is this all correct? If anyone can help me better understand all of this I would greatly appreciate it!

[azp7]

Hi Tim,

I am going to look for information about this!

But I recommend you (if you have access) to call Technical Support!

[WaldemarM · Accepted solution]

Hi Tim,

Your assumption is correct.

Waldemar