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[DPRG] Serial port programming question

Subject: [DPRG] Serial port programming question
From: Mike McCarty jmccarty at ssd.usa.alcatel.com
Date: Mon Aug 21 10:59:12 CDT 2000

On Fri, 18 Aug 2000, Clay Timmons wrote:

> I'm using Borland C/C++ on a laptop
> and have a serial port programming question.
> The laptop is connected to a motor controller
> via the COM1 serial port.  The communication
> is strictly one way, PC->motor controller, but I'm
> trying to add enhancements so that I can have
> two way communication, PC<->motor controller.
> I'm using  ouportb() command to send characters
> to the serial port which is working fine.
> I'm  trying to use inportb() to get characters back
> from the motor controller to the PC but it is not
> working.  I think my problem is that I'm trying to
> recieve characters from the transmit buffer.
> Does anyone know the segment and offset for
> the COM1 receive buffer?   Reciever status byte?

That information is not contained in memory. One accesses it via
inportb(), not via a segment and offset.


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