Protocol instrument - SPI Spy mode

[jfrenzel]

I am having trouble configuring the protocol tool to "spy" on an SPI bus. I have a custom design in the PL portion of a Zynq that acts like a SPI master to output three bytes and produces the correct waveforms shown in the "logic.jpg" picture. However, when I try to capture the same transaction using the Protocol tool, I get extra bytes of 0h00 after every "real" byte. (protocol.jpg).

Any thoughts?

[JColvin]

Hi @jfrenzel,

I believe this is because you have the Mode dropdown set to "Standard" rather than "3-wire".

With the Standard option, it looks like WaveForms still tries to read what is being transmitted on the DQ1 line; as there is no DQ1 line set, this ends up defaulting to all zeros.

Let me know if this does not resolve what you are experiencing.

Thanks,
JColvin

[jfrenzel]

That did the trick - thank you!