Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!ucbvax!aivax.radc.af.mil!marks
From: marks@aivax.radc.af.mil (David Marks)
Newsgroups: comp.sys.sgi
Subject: Serial Ports, DTR and RTS/CTS
Message-ID: <9104031623.AA18586@AIVAX.RADC.AF.MIL>
Date: 3 Apr 91 16:23:05 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 28

I want to connect 3 modems (actually NIU ports, but they LOOK and ACT like
modems) to our 4D/70GT (soon to be a 4D/340VGX).  We have the 6 serial port 
expansion interface, but those ports don't support DTR for detecting presence
of a connection; an attribute we require.  Ports 1-4 support DTR, but 2 and 3
are dedicated to the Buttons & Dials Box and the SpaceBall.

Questions: 
1.  Can the Buttons & Dials Box and SpaceBall be moved over to other ports
(5-10) which don't support DTR?

2.  Does the 6 serial port expansion interface for the 3xxVGX support DTR?

3.  Does it cost more than $5.00 of parts to support DTR (and the like) on a
serial port? (If not, why not provide that support on ALL serial ports, or
at least make it an option?!)

4.  Is there any reason to put a dumb terminal console on port 1 versus any
other port?

5.  Can stty be used to configure a port for RTS/CTS hardware handshaking?  
I've seen the net traffic on how to get it through a program, but I'd like to
avoid writing stty2.c  ...

Thanks

Dave Marks
Rome Laboratory
marks@aivax.radc.af.mil