Path: utzoo!utgpu!watmath!clyde!att!icus!limbic!gil
From: gil@limbic.UUCP (Gil Kloepfer Jr.)
Newsgroups: comp.sys.atari.8bit
Subject: Re: Serial Interface
Summary: Get the MPP driver or Rhandler
Message-ID: <394@limbic.UUCP>
Date: 20 Nov 88 05:57:20 GMT
References: <9657.192.forumexp@mts.rpi.edu> <22722@cornell.UUCP>
Reply-To: gil@limbic.UUCP (Gil Kloepfer Jr.)
Organization: ICUS Software Systems, Islip, NY
Lines: 33

In article <22722@cornell.UUCP> rbrown@svax.cs.cornell.edu (Russell Brown) writes:
>This can be done with a single chip.  There is a nifty little chip called the
>MAX232CPE which allows you to convert RS232 voltage levels to TTL levels with no
|>extra power supply (i. e. with just the five volts available on the joyport).

This is, indeed, a GREAT chip.  All you need is the chip, 5V, and 4 common
electrolytic capacitors and you're ready to go.  The chip "generates" the
~ +/- 12 volts for the EIA RS232 using a voltage doubler circuit on the
chip!  The power drain seems pretty low too :-)

|>This can be hooked up to two of the PIA pins in the joyport, as well as the
|>voltage lines.  Only problem with this approach is that it may require a
|>prohibitive amount of onboard software

There used to be a modem made by MPP which worked through the joystick
port.  Someone out there in net.land may have this and can slip it under
the rug to both of the askers.  Also around is something that I think
was called Rhandler which was a R: device driver that would drive the
joystick port modem (or 850 I think too!) using R: as a device name (so
you could use any terminal program).  Check Compu$erve or a local Atari
hacker for the latter (I think it may be public domain).

Of course, the best part about the joystick port modem idea is the fact
that you can use the disk drive and RS232 ports simultaneously without
any special suspension/resumption on the disk or RS232 port's part.

Hope this helps!

------
Gil Kloepfer, Jr.          U-Net: {decuac,boulder,talcott,sbcs}!icus!limbic!gil
ICUS Software Systems      Voice: (516) 968-6860 [H]   (516) 746-2350 x219 [W]
P.O. Box 1                 Internet:  gil@icus.islp.ny.us
Islip Terrace, NY  11752   "Life's a ...  well, you know..."