In sci.electronics.equipment Chris Campbell wrote:
I need to be able to look at the bits/bytes going back and forth on a
serial line.

This might be the PC-based tool you are using, but: see
http://groups.google.com/groups?selm...&output=gplain .
The blurb is still there; if the code isn't still there let me know
and I will mail it to you. A couple of outboard converters will
let you do 422 and 485. The code doesn't have address filtering but
you could probably add it - you'll need a DOS C++ compiler.

Matt Roberds