Newsgroups: comp.sys.transputer
From: jan@neuroinformatik.ruhr-uni-bochum.de (Jan Vorbrueggen)
Subject: Re: Clarification needed for T800 transputer and OCCAM
Organization: Institut fuer Neuroinformatik, Ruhr-Universitaet Bochum, Germany
Date: 08 Apr 94 12:07:58 GMT
Message-ID: <JAN.94Apr8130758@thalia.neuroinformatik.ruhr-uni-bochum.de>

The other point is that while, logically, Andy's right in saying that there's
one link going out and one link coming in that are seperate, physically both
logical links need the return path for the byte acknowledges. When a physical
link is used unidirectionally, the bandwidth in the other direction is free
and can be used for these. If the link is used bidirectionally, each
directions acks' cut into the other directions' data bandwidth - thus, net
data rate for two directions is (substantially) less than twice the
unidirectional data rate. If I remember the numbers right, it's something like
1.75 MByte/s vs. 2.35 MByte/s.

	Jan

