Path: utzoo!attcan!uunet!samsung!usc!snorkelwacker!spdcc!merk!alliant!linus!nixbur!nixpbe!peun11!josef
From: josef@peun11.uucp (Moellers)
Newsgroups: comp.lsi
Subject: Re: RS-232 5V (???), reference needed
Message-ID: <619@nixpbe.UUCP>
Date: 14 Nov 89 07:33:36 GMT
References: <9820@etana.tut.fi>
Sender: bnews@nixpbe.UUCP
Lines: 26

nurmi@haapana.tut.fi (Nurmi Jari) writes:


>I am looking for a standard serial interface which could be implemented
>using 0-5V CMOS devices. I have heard some second hand information that
>there EXISTS some RS-232-xxx standard that might do.

>If someone out there knows such standard, please let me know! I would be
>pleased to have a) a verification of the existence of the 5V version
>b) the identification of the standard (by what name can I find it) and then
>c) what is the reference where I can read the specifications of it.

There are two ways to get away with 5V only:

1 Stick with the "original" RS232C (a.k.a. V.28) and use chips
  manufactured by Maxim: the MAX23x series chips.
  They incorporate a 5V to +-10V converter which works just fine.

2 Take the RS422 standard. It's a symmetric interface which uses two
  wires for each transmission line, but everything works with 5V.


Josef Moellers					| Nixdorf Computer AG
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