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From: U39648@uicvm.uic.edu (From The Mind Of)
Newsgroups: comp.sys.ibm.ps2.hardware
Subject: Re: IS P2/2 70 or 80 UART socketed?
Message-ID: <91113.201729U39648@uicvm.uic.edu>
Date: 24 Apr 91 01:17:29 GMT
References: <1991Apr23.152424.4993@midway.uchicago.edu>
Organization: University of Illinois at Chicago
Lines: 37

>Does anyone know if the 16550 in PS/2 model 80-111 or 70-121
>is socketed, so it can be replaced with a 16550A?

Well, those models contain logic in VLSI chips that are *not* ICs but are
surface-mounted on the motherboard that handle the serial RS-232C port.  The
functional interface is that of an NS16450, but it is in fact contained in
some custom IBM VLSI chips.

If you want a 16550A controlled serial port on those IBM PS/2s, you'll need
to get a serial port card that actually contains one or contains a chip that
can be replaced by one.

If you need communications that take even less CPU time than a serial port
controlled by a 16550A, try:


Extended Serial Port for PS/2s

 From: Advanced Microcomputer Systems, Inc.
       1321 NW 165th Place
       Fort Lauderdale, FL 33309
Phone: 1-305-975-9515 / 1-800-972-3733
       1-305-975-9698

This is a serial port bus-mastering Micro Channel adapter that confirms to
the intelligent extended serial port (ESP) specifications proposed by Hayes.

There is a Windows 3.0 driver for ESP serial ports too.  It's much better
performance that 16550A FIFO serial ports.

- Darius
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