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The big question is why the huge PC104 interrupt rates on vipers at a1, a5, a8 and m21 vipers. Previously traced this to a floating CTS/RTS line, but I don't think that is the current reason. Saw high PC104 interrupt rate on m21 even with the ribbon cables disconnected from the Emerald headers! Will have to investigate those systems back in the lab.
The only titans with PC104 serial are a3 and m22. They're both OK.
Vipers at a2, a6 and c20 are OK.