Set up a capture according to the directions at https://blackmesalabs.wordpress.com/2016/10/24/sump2-96-msps-logic-analyzer-for-22/ .

You should see a trace that looks like this:

Note that there are a few issues with the SUMP2 viewer.  If the capture spans a large number of clock cycles, it can take a very long time to render, even if there are relatively few transitions.  Also, it stops rendering each signal after the last transition.  I prefer to export to VCD, then import into GTKWave.  This same capture looks like this:

Here we can verify that the "strobe" inputs properly XOR the data_in bits into the internal "state" bits.