Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!lll-crg!rutgers!clyde!cuae2!gatech!akgua!mtune!mtunb!dmt
From: dmt@mtunb.UUCP (Dave Tutelman)
Newsgroups: comp.sys.att
Subject: Re: IBM-PC keyboard for 6300 has anyone done this?
Message-ID: <788@mtunb.UUCP>
Date: Sat, 29-Nov-86 10:39:18 EST
Article-I.D.: mtunb.788
Posted: Sat Nov 29 10:39:18 1986
Date-Received: Mon, 1-Dec-86 06:39:36 EST
References: <1519@ihlpl.UUCP> <328@neoucom.UUCP>
Reply-To: dmt@mtunb.UUCP (Dave Tutelman)
Distribution: net
Organization: AT&T Information Systems - Lincroft, NJ
Lines: 54

In article <328@neoucom.UUCP> wtm@neoucom.UUCP (Bill Mayhew) writes:
>
>I don't think that merly rewiring the plug on an IBM keyboard
>is adequate to get it to work with the 6300.  It looks like the
>baud rate is different to me, as I couldn't get it to work.  
	Actually, the whole protocol is a little different.  A transposition
	cable isn't enough to solve the problem.

>Two of
>our 6300s here have replacement keyboards.  One machine has an AT&T
>version of the Keytronic 5151 which even comes with a db-9 on the
>end of the cord.  
	I've used the Keytronics.  It's pretty nice, and I never noticed
	any incompatibilities.

	You might also try AT&T's new 302 keyboard, with better key placement
	and size than the original 301.  I'm using it right now.

>...
===============================================
>By the way, one of my older 6300's that was in the days of 256K and
>10 meg drives did indeed come with all the chips soldered to the
>board.  The only socket in the machine was a blank one for the
>8087.  We flamed the AT&T salesperson, who produced the AT&T memory
>expansion card to get it up to 512K.  I was suprised when I
>observed that the AT&T memroy card has to go in one of the slots
>that has the short socket near the front of the machine, although I
>don't see any reason why you couldn't use one of the expansion
>cards for regular pc-compatibles.
	Actually, the only reason is speed.  The speed ordering is:
   -	FASTEST - on the motherbaord.
   -	SLOWER - The plug-in board from AT&T gives a wait-state on each
		access.
   -	SLOWER STILL - Commercial plug-in boards using only the PC-bus.
		They don't use the full 16-bit capacity of the 8086.
		Remember that the PC and XT are 8088s with an 8-bit
		data bus.  Thus all their memory accesses are single bytes.
		The 6300's speed advantage derives in part from a two-byte
		data bus, with the extra byte on the "short socket".

>
>  --Bill
>
>(wtm@neoucom.UUCP)

---------------------------------------------------------------
       ---===		Dave Tutelman
    -------=====	Physical - AT&T Information Systems
  ----------======		Room 1K218
 ==--------========		307 Middletown-Lincroft Rd.
  ====---=========		Lincroft, NJ 07738
    ============	Logical  - ...ihnp4!mtuxo!mtunb!dmt
       ======		Audible  - (201)-576-2442
---------------------------------------------------------------