Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!mips!prls!gordon
From: gordon@prls.UUCP (Gordon Vickers)
Newsgroups: comp.sys.ibm.pc.programmer
Subject: How do get COMx to do 19,200 baud
Message-ID: <32894@prls.UUCP>
Date: 1 Mar 90 17:10:00 GMT
Reply-To: gordon@prls.UUCP (Gordon Vickers)
Distribution: usa
Organization: Philips Research Labs, Sunnyvale, California
Lines: 36


        I am considering the use of several IBM ATs to replace some
   ageing in-house designed boards.  I am no expert on PC's but from
   my initial study, it seems that my main problem will be trying to
   get an RS232 serial port to communicate at 19,200 baud.  One solution
   would be to find a serial card that contains a uP as well as an
   input and output buffer thus supporting the ability to read/write
   as to a file.  Does such an animal exist ?

       My specific needs for this project :
            allow keyboard input
            text only  output to monitor
            allow stdin and stdout to be redirected to a serial port
              (normal state for this application), baud rate would be 2400.
            bidirectional second serial port at 19,200 baud, RS422
              (preferred) or RS232
            application program to load and run automatically after power
               is applied.
            possiable future addition of a third serial port at some lower
               baud rate (1200 or 2400 baud)
            possiable future additions of a hard disk, and eathernet (802.3)

       What disturbs me about the AT is that the keyboard has such a high
     interupt priority. Is this changable at the hardware level or software ?
     If software, at what level is the software change made (boot, BIOS,
     kernal )?

       Any recommendations on how to do 19,200 baud on a serial port? One
     advantage to this problem is I'll have some advanced warning that
     no more than 80 charectors will soon need to be read.

   Thanks for any assistance,
Gordon Vickers 408/991-5370, at Signetics  (Sunnyvale, California, USA )
{mips|pyramid|philabs}!prls!facv01!gordon       ** All disclaimers apply **
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