Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!emory!mephisto!ncsuvx!news
From: rnf@shumv1.uucp (Rick Fincher)
Newsgroups: comp.sys.apple
Subject: Re: synchronous comm. from GS serial port?
Message-ID: <1990Mar7.043041.11195@ncsuvx.ncsu.edu>
Date: 7 Mar 90 04:30:41 GMT
References: <9003061630.AA26847@mwunix.mitre.org>
Reply-To: rnf@shumv1.ncsu.edu (Rick Fincher)
Organization: NCSU Computing Center
Lines: 26

In article <9003061630.AA26847@mwunix.mitre.org> mcgurrin@MWUNIX.MITRE.ORG writes:

>Is it possible to use the standard GS serial ports to run synchronous 
>communications, specifically HDLC?  As I understand it, Appletalk is a
>synchronous multiuser protocol, so I would assume the answer is yes, but
>have never seen the question addressed.  

Yes, you can.

>
>Second, I assume, but maybe incorrectly, that one could not use the firmware
>calls to do this, but would have to talk directly to the chip.  If so, can
>I access the full capabilities of the comm. controller chip, in particular
>automatic CRC generation and checking?  Is this documented anywhere?

You are correct again.  The hardware reference manual has the addresses for the
Zilog 8530 chip ports, you can get an 8530 reference manual from Zilog or a
parts house.  If you get the Zilog version of the manual, it has C source code
listings in the back of the manual that demonstrate the proper methods of 
setting up the chip.

>
>Thanks to anyone who can help.

Rick Fincher
rnf@shumv1.ncsu.edu