From: "Mark Dormer" <markdormer@one.net.au>
References: <375BB307.A0951D6D@cs.lubasa.es>
Subject: Re: Accessing com ports under Windows
Date: Tue, 8 Jun 1999 14:09:39 +1000
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Add this to system.ini, in the [386Enh] section:

Com<n>AutoAssign=0

COM<n>AutoAssign=<number-or-seconds>

Default:  2
Purpose:  Indicates the contention detection values for each
          connected serial port. These values are used by
          Windows to determine how to arbitrate requests for
          the use of a device by more than one application,
          at least one of which is a non-Windows
          application. If the value is -1, Windows will
          display a warning message that asks you which
          application should be given control of the port.

            IF the value is 0, any application can use the
          device at any time.

            If the value is a positive
          integer less than 1,000, this value represents the
          number of seconds after an application stops using
          the device before another application can use the
          same device.


--
Mark Dormer

http://www.angelfire.com/biz/serenitymacros

Last Updated 5/5/99

Jesus Martinez de la Cruz <jmartinez@cs.lubasa.es> wrote in message
news:375BB307.A0951D6D@cs.lubasa.es...
> Hi to all.
>
> I have two old MSDOS independent applications that need to run at the
> same time under Windows. Both use the same serial port, but never at the
> same time.
>
> The problem is that when one first sends or receives data from serial
> port, Windows locks that port and no other application can use it.
> Closing the application doesn't unlock it, it is not unlocked until the
> DOS shell is closed.
>
> I'd like to know if does exist any method that allows telling Windows
> that the port is not used anymore and it can unlock it, or any method
> for the in turn use of the port from two DOS applications.
>
> Thanks in advance.



