Mapping of Signal USB-8451 problem

I recently bought a USB-8451 used to try some Labview SPI/I2C development. I found that when I create a simple VI to write and watch the signals on a PC based Logic Analyzer, I see that the SCLK, MOSI lines are reversed. I checked that I have the correct connections to the Analyzer and confirmed that the pins are correct in the 8451 user manual. If someone else found this? I've attached screenshots of my VI and Logic Analyzer. I tried the 8451 examples and the result is the same, the SCLK appears on the MOSI line. I don't think it would be a real issue of what I want to do, but I find it strange. Am I missing something?

Catherine,

I found the problem. After the change to a faster USB port and to monitor and increase the frequency of sampling, I was able to get the SCLK appear correctly. I can say that this problem is resolved,

Thank you

Andrew

Tags: NI Software

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