Xref: utzoo comp.sys.amiga:27796 comp.sys.amiga.tech:3187
Path: utzoo!attcan!uunet!lll-winken!ames!killer!elg
From: elg@killer.DALLAS.TX.US (Eric Green)
Newsgroups: comp.sys.amiga,comp.sys.amiga.tech
Subject: Re: CheapNet (SneakerNet ?)
Message-ID: <6783@killer.DALLAS.TX.US>
Date: 14 Jan 89 07:13:50 GMT
References: <5748.AA5748@heimat>
Organization: The Unix(R) Connection, Dallas, Texas
Lines: 47

in article <5748.AA5748@heimat>, sneakers@heimat.UUCP (Dan "Sneakers" Schein) says:
>   Why? I have two Amiga 2000's sitting here, both using the serial ports (one
>  running a BBS 24 hrs, the other running UUCP 3-4 hrs). What id like to do is
>  run a cable between the PARALLEL port of both machines (similar to a RS-232
>  null modem cable). Then using an AUX: like device and special terminal prog-
>  ram access machine B from machine A. 

I just looked at the schematics in the back of my A500 manual, and
it's quite possible indeed. Almost all the pins on the parallel port
are connected straight to the CIA I/O pins, meaning they're
bi-directional. Including things like "Paper Out", etc. You could
easily do something like, say: use 8 pins for data input/output. Use
Strobe/Ack for clocking the bytes (suitably cross-wired cable, since
at first glance one appears to be hardwired interrupt-producing input
& one hardwired output). Use, HMM, BUSY for direction turnaround
(since this is a half-duplex port, after all). Set up a suitable
low-level protocol.  Use DNET or something like that, for the
higher-level protocol. Presto. Can at least transfer files that way,
I don't know about other stuff.

Hardware, then, is fairly simple. For software, would have to write a
network.device which grabbed the printer port from the
parallel.device, have something wedged into the interrupt chain to
handle handshaking, and then, if desired, a Dos-level handler a' la
AUX:. 

I have two Amigae here, too, so I'll have to take a look & see exactly
how difficult it'd be. I need to learn how to write device drivers
anyhow... I've done something of the sort before on the 64, but the
Amiga is no 64.

>   I know this method is limited by allowing for only one way communications
>  with no file transfer, but thats all I need. My desk is just too small for
>  2 keyboards and 2 monitors!

The only limit would be that offered by your networking protocol. As
for the problem with your desk, I had the same problem. When we went
house hunting, one priority was a whole room just for the computers &
electronics junk. We thought we'd never use that much space... three
walls covered with rough plywood tables (~$30 total), & a ton of
shelves. Maybe two square inches of surface are visible now.

--
Eric Lee Green    ..!{ames,decwrl,mit-eddie,osu-cis}!killer!elg
          Snail Mail P.O. Box 92191 Lafayette, LA 70509              
Netter A: In Hell they run VMS.
Netter B: No.  In Hell, they run MS-DOS.  And you only get 256k.