From: jjmcwill@mtu.edu (Jeff McWilliams)
Subject: Re: 800XL expansion port
Organization: Michigan Technological University
Date: Wed, 6 Jan 1993 07:33:16 GMT

In article <C0F4M1.609@usenet.ucs.indiana.edu> jbmorris@bronze.ucs.indiana.edu (Jeff Morris) writes:
>What is that parallel port on the back of 800XL's for?  I was told when I
>bought mine (1984) that it was "for future use".
>How would one send information to that port?
>
>Let me tell you what I want to do:
>I want to transfer text files created in AtariWriter over to IBM.  I know you
>have the files at the archive for reading Atari disks on IBM's, but can you do
>it another way?  For one, I don't have beyond DOS 3.0 on Atari, but I've got
>MS-DOS 5.0 for IBM.
>Could I send ascii characters out of that port or the printer/all-purpose
>port and into some IBM port?  I just want to put these files onto my hard drive
>as text files.
>Or is the easiest way to do something like this to use those files?
>But you have to hook up your Atari disk drive to your IBM or something?
>I have a 1050 Atari disk drive.
>

Jeff,

Okay, the Parallel Bus Interface can allow you to plug in several
devices, the K-Products (formerly Supra) Interface, an ICD MIO, 
or the Computer Software Services Black Box.

The K-Products interface, from what I know of it, is a SCSI hard disk
drive interface.

The MIO is a SCSI/SASI hard disk interface, printer interface, 
modem interface, and has RAM which can be used as a printer spooler and/or
a RAMDISK.

The Black box has a SCSI/SASI hard disk interface, modem interface, 
printer interface, optional 64K RAM for a printer spooler, optional
floppy disk drive interface, and has a 6502 monitor/debugger, and an
optional disk editor/fixer.

BEST Electronics sells an MPP Microport Experimenter's kit that has a 
Peripheral Interface Adaptor chip on it, so that you can experiment
with all sorts of electronics projects with it.  The book shows how
to biuld an LED Clock, and a simply EPROM burner.  You could also use
it to experiment with Analog to Digital conversion, Digital to 
Analog conversion, sound digitization, or a do it yourself printer
interface.  It's only limited by your imagination.

Bob Woolley of the San Leandro Computer Club also did a Parallel Bus
hack called the PIO interface, which took your expanded 256K computer, 
and created two 90K disk drives out of it.  You could then copy, say,
an Infocom game into the Ramdisk, and boot and run the Infocom 
game totally out of RAM.  I didn't do this hack, but it sounds really
neat.  Infocom games were notorious for always accessing the disk drive 
all the time.  These games would be blazingly fast with the PIO device.

As far as trasferring files between your 8 bit and your IBM PC.
Well, you COULD build something yourself on the PBI, and write your
own software, to communicate with the IBM, and put the IBM's printer port
in INPUT mode... but geeze... it would be just as easy to bild the 
SIO2PC interface, which plugs into your IBM and your Atari, and 
lets you create Atari floppy disk "partitions" on your IBM hard drive..
then you  simply write to the IBm hard drive from your Atari, as if 
it were a floppy disk.

Another alternative would be to get a modem interface, and run a 
null-modem cable between your Atari modem port and your IBM modem 
port.  Then use something like Kermit to transfer files at 9600
baud. 

Those are pretty much THE alternatives.  Hope this helps.

Jeff

-- 
Jeff McWilliams  jjmcwill@mtu.edu  EE Engineer --> Michigan Tech. 
Leaves Turning, falling, withering
Wind blowing, rustling, chilling
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Newsgroups: comp.sys.atari.8bit