Path: utzoo!mnetor!uunet!husc6!think!bloom-beacon!tut.cis.ohio-state.edu!ut-sally!utah-cs!utah-gr!uplherc!sp7040!obie!wes
From: wes@obie.UUCP (Barnacle Wes)
Newsgroups: comp.sys.atari.st
Subject: Re: atari to appletalk quest
Message-ID: <85@obie.UUCP>
Date: 24 Mar 88 09:16:16 GMT
References: <8803071434.AA04788@ucbvax.Berkeley.EDU> <512@uhnix2.UUCP>
Organization: the Well of Souls
Lines: 22
Summary: ST can't generate AppleTalk speeds?  Hah!

In article <512@uhnix2.UUCP>, uace0@uhnix2.UUCP (Michael B. Vederman) writes:
> Unfortunately, this cannot be done with the ST as it stands without external
> hardware (probably thru the DMA port).  The reason for this is that the
> AppleTalk network uses a baud rate far greater than the ST can produce.

Not true.  The MIDI port can be easily driven at 500K bps, much faster
than Apple's LocalTalk hardware, which is essentially an RS-422.  If
you play with the baud rate generator on the RS232 port, you might be
able to get the kind of speed LocalTalk uses.

The ST's RS232 port is driven off the USART built into the 68901 MFP
chip.  The clock for this USART is Timer D on the 68901.  By
programming the 68901 carefully, using the Timer D registers and the
USART Conrtrol REgister (bit 7), you _might_ be able to build a
LocalTalk connector.  Software to use it is quite another question :-).

	Wes Peters
-- 
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