Path: utzoo!attcan!uunet!pyrdc!pyrnj!rutgers!gatech!ukma!simon
From: simon@ms.uky.edu (Simon Gales)
Newsgroups: comp.sys.ibm.pc
Subject: Re: What is the difference between XT and AT serial ports
Message-ID: <10588@s.ms.uky.edu>
Date: 18 Nov 88 00:38:40 GMT
References: <3078@dalcs.UUCP> <1232@unccvax.UUCP>
Reply-To: simon@ms.uky.edu (Simon Gales)
Distribution: na
Organization: U of Kentucky, Mathematical Sciences
Lines: 27

In article <1232@unccvax.UUCP> mru@unccvax.UUCP (Markus Ruppel) writes:
>in article <3078@dalcs.UUCP>, lane@dalcs.UUCP (John Wright/Dr. Pat Lane) says:
>> I've read that the serial port in the IBM PC and XT is based on the 8250
>> chip while for the AT, a 16450 chip is used.  In my AT clone, I notice the
>> serial board has an 8250 on it which seems to work just fine.  I'm wondering
>> what the difference between these two chips is, 
>From the National Semiconductor data sheet:
>
>	"The NS16450 is an improved specification version of the INS8250A
>	 Asynchronous Communications Element (ACE). The improved specifica-
>	 tions ensure compatibility with the NS32016 and other state-of-the
>	 -art CPUs. Functionally, the NS16450 is equivalent to the INS8250A."

I believe that the 16450 has a larger internal buffer and can also handle
higher baud rates.

>Markus Ruppel

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<---   Simon Gales@University of Ky                 263-2285/257-3597   --->
<---            [ simon@ms.uky.edu ]  |  [ simon@UKMA.BITNET ]          --->
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<---   Simon Gales@University of Ky                 263-2285/257-3597   --->
<---            [ simon@ms.uky.edu ]  |  [ simon@UKMA.BITNET ]          --->
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