Xref: utzoo comp.protocols.appletalk:5008 comp.sys.mac.comm:2111
Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!tut.cis.ohio-state.edu!unmvax!uokmax!d.cs.okstate.edu!minich
From: minich@d.cs.okstate.edu (Robert Minich)
Newsgroups: comp.protocols.appletalk,comp.sys.mac.comm
Subject: Re: do I need phone net connectors? <summary>
Message-ID: <1991Jan8.112500.14143@d.cs.okstate.edu>
Date: 8 Jan 91 11:25:00 GMT
References: <1991Jan8.090043.25113@sics.se>
Organization: Oklahoma State University
Lines: 24

by boortz@sics.se (Kent Boortz):
|# One person said he had successfully used an IW II cable to run Appletalk
|# from one Mac to another, but the general concensus was "Don't bother
|# trying". One person from TOPS wrote and said I would void my warranty
|# with TOPS if I tried that, and may even damage my Appletalk ports.  So I
|# guess I'll be ordering a couple phone net connectors!
|
| This is very strange in my opinion. An ImageWriter cable is a standard
| serial cable for mac and is intended for connection of two RS-422 ports.
| There should be no difference electrically connecting a mac to mac, mac
| to modem, mac to LaserWriter or mac to ImageWriter.
 
A straight null-modem cable should do fine for two LocalTalk devices however,
Kent is wrong about (mac<->mac) == (mac<->modem) == (LW|IW<->mac). [Did
that come out right?]  The exception is the modem. Serial devices come in
two flavors, Data Terminal Equipment (DTE) and Data Comm. Equ. (DCE).
When wiring DTE<->DCE, the pins labeled Tx (transmit) on both devices
are connected together while DCE<->DCE cables have Tx<->Rx wiring,
eliminating the need for a modem, thus the null-modem cable.
-- 
|_    /| | Robert Minich            |
|\'o.O'  | Oklahoma State University| "I'm a newcomer here, but does the
|=(___)= | minich@d.cs.okstate.edu  |  net ever lay any argument to rest?"
|   U    | - Ackphtth               |                    -- dan herrick