Newsgroups: comp.sys.transputer
From: Mark Sandford <msandford@delphi.com>
Subject: Re: Connecting 2 Transputer Boards (in diff. hosts)
Organization: Delphi (info@delphi.com email, 800-695-4005 voice)
Date: Wed, 28 DEC 94 19:43:04 -0500
Message-ID: <5s-b4EI.msandford@delphi.com>

I have done something similiar, with inmos/transtech B008's.  I'm not familiar
with your set setup so thier may be differences that I'm not aware of.  In my
2 rack mount chasis) and run a
cable (links only) to a second PC.  You indicate that you can see the full netw
network from either pc.  This suggests to me that you have the reset from the se
second pc connected to the network in the first.  As far as resetting goes this
is ok as reset is a simple input, but the problem is that you reset your
main system to load code onto the network and then load code (reseting)to
load your monitor on to the second pc which also resets the processors in
the first pc (BAD).  I'm not familiar with your specific hardware but
with most transputer boards, atleast those with provisions for host
interfaces you must select where reset comes from either host or network down.
I see two possible solutions.
A) If you can set the system services on your single processor board to being
input (network down or similiar), you can use this processor as the last
member of the network.  You will not beable to load code from the second
pc but you can put the server into server link mode and write out but
no code will be directily loaded to this processor (not a great solution,
but ought to work.) use the /SS option with the server and it will respond to
the link (host interface) without running any code.
 
B) the second solution is the more commonly accepted solution and the one
which I would suggest to you.  In this situaltion you should only run a
link cable from the network to the single processor (not reset, analyze or
error).  Now you will run a program on your network and write out to a blind
link that is the external processor.  The single processor will run a monitor
program that waits for data to magically appear on its input link.  Niether
the network or the single processor will know of the others existance since
a processor must be reset to show during a network search.  Data can be passed
between the network and single processor as usual they just write or read to a
link for which no code from thier side has been loaded.  This works well,
but there is no way that I know of to see the other machine's processors
directily, although data will pass as ussual.
 
Another problem that you may have not considered is that links assume a common
ground between any two communicating processors.  In general this is not
a problem but care should be taken ensure that both machines have a common
ground, this is ussually done by simplly running a wire between a chasis
ground in either machine, differential drivers are another solution (RS422).
 
 
Hope this helps.

