This thread has been very helpful as I am trying to debug a 1680AD. I purchased the 1680AD off ebay, and it is an early variant with the Tyan motherboard. It has a working Windows 2000 OS plus version 1.40 of the LA software. The unit boots and is able to connect to the LA unit over firewire, and I was successful in using it to capture some 68030 signal traces.
The issue I have is the unit will only work for between 10 and 60 mins before it faults with ' Lost Communication with the LA'. I replaced the firewire cable, as well as the firewire card, and that made no difference.
In an attempt to debug further I built a newer Windows 7 PC and installed the latest 5.90 software from Keysight as well as a TI1394 firewire card. That new machine was able to connect to the LA module, although I had to upgrade the firmware on the module from 0.90 to 1.03 first.
From the new machine the behavior is the same - the LA works for a bit, but if you run a self test loop it will always eventually fail some test. The actual failed test is random, and sometimes you can run the same test again and it works.
It appears there is a problem with the communications side of the LA card that causes it to drop or corrupt data occassionally.
Has anyone seen this particular problem before? I did pull the LA board and inspect it, but there was nothing obvious in any of the parts or traces. It is a Rev A board, which is not surprising given the Tyan motherboard.