Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!usc!apple!portal!cup.portal.com!R_Tim_Coslet
From: R_Tim_Coslet@cup.portal.com
Newsgroups: comp.arch
Subject: Re: 1620 Opcode Selection
Message-ID: <35060@cup.portal.com>
Date: 20 Oct 90 05:04:52 GMT
References: <34880@cup.portal.com> <7044@uwm.edu>
Organization: The Portal System (TM)
Lines: 39

In article <7044@uwm.edu>
	jgd@convex.csd.uwm.edu (John G Dobnick) writes...
>From article <34880@cup.portal.com>, by R_Tim_Coslet@cup.portal.com:
>> 
>> The 22 (sub opcode) doesn't correspond to any character.
>> 
>> I have the book right infront of me.......
>
>Unfortunately, the book is wrong.  (See... you _can't_ believe everything
>you read!)
Yes you can........   you just have to read the RIGHT part    :-)
>
>Based on actual experience (the venerable 1620 being my "first computer"
>he said, waxing nostalgic), and checking the penciled in notation on
>my "yellow card", a 22 would print (on a 1443 lineprinter) as a
>"record mark".
Well, I looked this up and my book lists that too; however it is "hidden"
in the text discribing the printer (and didn't work on early models)...

       "A [record mark] may be printed by PRINT ALPHAMERICALLY (PRA-39)
	instructions on 1620 Model 1 serial number 10701 and above, and
	all 1620 Model 2's by the undefined character code 22. A 22 will
	not terminate data transfer and is not detected as a [record mark]
	for other operations."
>
>  yellow card -- IBM 1620, Model 2, Reference card.  Form X26-5852-1

BTW, my first computer was also the 1620 (but I used a Model 1) and it
didn't have a printer (we punched printouts on cards and printed them
on an old "accounting machine", IBM 407 if I remember right) when I used it.

>Now... does anyone out there remember the IBM 1710 ???
No... what was "interesting" on that machine?


                                        R. Tim Coslet

Usenet: R_Tim_Coslet@cup.portal.com
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