With the latest firmware, the screen doesn't go white like it used to but the Nano locks up. It will not accept USB commands and requires a power cycle to recover.
Try this version
I was planning to use this version while I work through my regression tests. I have started adding a report generator and increasing some of the tests I run. I will report the problems as I find them. If you want to try to correct them as I find problems, I would be willing to work with you to run your changes through my regression tests.
Problem 1
Setting the Center frequency to 750MHz, then set the Span to 1500MHz. Request the Frequency. The firmware returns only 100 data points rather than 101. I would expect the Nano to always send 101 data points. This problem is reproducible.
Problem 2
Setting the Start frequency to 0MHz, the Stop to 1MHz. Request the Frequency. The firmware returns a starting frequency of 10KHz rather than the expected 50KHz. The number of data points is correct. I would expect the Nano to limit the lower frequency to 50KHz, or there should be a document explaining that the lower limit is now 10KHz. This problem is reproducible.
Problem 3
Screen still leaving random artifacts from previous scan when using the Smith Chart. This problem is reproducible and appeared in the firmware that was supplied with my Nano. I have yet to see firmware that does not have this problem.
Problem 4
After programming the new firmware into the Nano and running a calibration, the calibration appeared corrupt. An open was on the left side of the screen and a short was on the right. Applying any load would be unstable when looking at the display. The frequency range was set to 0.05 to 900MHz prior to calibration. A reset was ran prior to calibration. Attempting to repeat the calibration corrected the problem. I have not attempted to repeat this condition.
Problem 5
Programming a start of 50KHz and an stop frequency of 1500MHz. Request the Frequency. The firmware returns the correct frequency for the first data point. Looking at higher frequencies, there is an error between various firmware. For example, some will report 1500 for the last data point where others report 1499.99995. For a given version of firmware, it will return predictable values. This problem is easy to reproduce.