IIRC, I don't believe that either the 925 or 950
handled VT100/ANSI
 protocol.  I believe you had to go to the 922 for that. 
I used to use TeleVideo heavily.  The 950 was my favourite, but I also
used the 925, and I can confirm that neither one does X3.64 (nor even
that foundation X3.64 built on, whose name I'm having trouble recalling
- X3.41 maybe?).
I don't think I've ever seen a 922, so I can't speak to that part.
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