Delay time of NI-9227 C module

[AndyKr]

In the manual of the 9227 module from 2010 it is stated a delay time of 38.4/fs+3.2us, on the knowledgeBase article here  (Why Is My Data Delayed When Using DSA Devices?) it is 40/fs+3.2us. Which one is the correct one??

[charlie87]

Hi AndyKr,

did you find the answer ?

[MitchBrown]

Hey Charlie,

I'll be surprised if you get a reply on a 7 year old thread, but I'm adding this as a note.

The manual is almost always correct as they are created once and then left, whereas Knowledgebase articles are updated as more information is found that is relevant.

A good example is the article that Andy linked, it was last updated only 2 months ago and no longer references the module that this question relates to. As such, the value from the datasheet should be treated as correct.

Hope this helps!

Mitch

[Jean-Louis]

Hi,

Beware of NI-9227 Datasheet !!!
(last version is dated July 2014).

Why NI used such a stange notation to say "Input delay = 40.01/fs + 2.9 µs"  ?
The result is a factor 100 error if you understand the formula as 40 * 5/512 instead of 40 + 5/512.

There is a hudge difference !

Exemple

if fs=2 kHz, you may think that the input delay will be 0.19 ms. In reallity you will observed an input delay of 20.0 ms !

If you have synchronisation considerations in your application, you should be very carefull with this subject.

Hopping that this datasheet will soon be corrected...
I will checked this point personaly.