Bragga,
Apologies, I didn't make myself clear enough.
I'm perfectly familiar with EMI, EMC, etc.
I'm also familiar with automatic flight control systems architecture,fly-by-wire and suchlike.
My question was specifically aimed at the electronic implementation in current FBW systems of the link between flight control computers and elevator controls: bus type, interfaces, etc.
John,
I only quoted those snippets because they were what triggered my realising, that my "knowledge base" was getting thin on the ground since ARINC 429 (and things like Wx radar and DFDR buses).
CJ