Date : Fri, 30 Oct 1992 15:23:51 GMT
From : destroyer!caen!nic.umass.edu!hamp.hampshire.edu!jmolinari@gatech.edu
Subject: Re: 5v out serial port
In article <1688E9FA1.DHBHM@nervm.nerdc.ufl.edu>, DHBHM@nervm.nerdc.ufl.edu
(Bruce H. McIntosh) writes:
> In article <1992Oct17.150342.1@hamp.hampshire.edu>
> jmolinari@hamp.hampshire.edu writes:
>>Anybody had their serial port NOT put out the 5 volts it's supposed to?
>>Anybody care to take a guess at how diffucult it would be to fix?
>
> If your serial port is a real, live RS232 (RS232 standard - there's a front
> runner for oxymoron of the month! :-) ), it is NOT supposed to put out 5vdc!
> RS232 works with a voltage swing of +/- 9vdc.
>
Well, the "5 volts" was supplied by a friend of mine who may or may
not know what he's talking about, but certainly knows more than me. What I
meant to say is that, whatever the voltage is, it's not putting out the right
kind of juice.
I have a Hayes compatible modem which, when I plug it into my Amiga,
makes a sort of "squelch", indicating that the serial is supplying it with
eliectricity. It does no such thing when I plug it into the Kaypro, and,
not surprisingly, does not respond to Hayes-commands (ATH0, etc.). It just
sits there.
Parting from this, I'll rephrase my original question:
IS the +/- 9v output in the Kaypro a sufficient standard to assume
that my Amiga puts out the same quantity? If this is so, then the serial
on the Kaypro IS damaged, as the modem receives no power.
You've probably noticed by now that I don't have a voltage meter.
I know it's gauche to use a hayes-comp. as a meter (or LED) for my serial
ports, but hey... :-)
jmolinari@hamp.hampshire.edu