SPI write delayed by 44usec

[ggaryt]

Hello,

I'm seem to be having a problem with a SPI write using the NI-8451 POD with a SPI clock of 1MHz.  The read is only 8usec after chip select go low but the write is 44usec after the chip select go low ( I have attached scope pictures).  I have taken and earlier version of this write subVI and the only change was from writing a 32 bit registers to an 8 bit registers which should have speeded it up.  Has anyone seen this before, I don't have this much delays in the earlier write subVI and it is a remake of the example (SPI advanced write script).  I'm using LabVIEW version 8.0 I also included the spi write script block diagram for your review.  Let me know what else you'll need to help diagnose this delay problem.

Thanks,

Gary Tyrna

[ManLongAtNI]

Hello Gary,

If I understand it correctly, you are seeing the write occur 44usec after the chip select goes low. It sounds as if this occurs only in your piece of code but not from and SPI example write script. If that is not the case, do you see the same behaviour from either our basic or advanced examples from the Example Finder.