Have I killed my 7i84?

Here is also a 7i97 I am setting up for my lathe where I can give it a try.

Duh, I am such a dumbass. I have a 7i96 on the mini lathe I can test it on. Thanks.
Mark

I just tested the 7i84 on the 7i96, and it works fine. So now that I have all the I/O connectors pulled, and a new CAT 5 cable made up, I will try it again on the 7i77, with no I/O connected, and a separate field PSU.
[5 minutes later]
Okay, with a new CAT 5 cable, and a different Field PSU powering the 7i84, the 7i77 and 7i84 work fine together, which is really good news, so it looks like I failed to kill them (so far). Now I need to trouble shoot what caused them to stop playing nicely together in the wiring config which worked for the last 18 months.
I can feel in my bones where this is going. There is going to be something really dumb, like me conecting Field to an earth pin or something.
Mark

After being more systematic with the trouble shooting, it looks like the 7i77 is damaged, but only the driver IC (or whatever is in there) of TB8-15. Once I moved the switch from that pin to another, I am back in business.
Thanks for your help.
Mark