I'm muddling thru the 16F84 and I understand MicroChip does not intend to
support the TRIS instruction in future products (is it usable in the
16F877?).

So in place of a TRIS command I would simply use a MOVWF   TRIS(A,B,etc)
assuming that W is loaded with the desired mask.

Thanks,
Kev
HKC Inc.