mmm@cup.portal.com (Mark Robert Thorson) (10/11/90)
As I recall, the 1620's add and multiply opcodes corresponded to the character codes for "a" and "m". Maybe some old geezer could confirm that :-)
mmm@cup.portal.com (Mark Robert Thorson) (10/14/90)
I've been informed that the opcodes for add and subtract on the 1620 correspond to the character codes for + and -. I was probably thinking of the 1401 (or whichever model had an assembler called AUTOCODER).
R_Tim_Coslet@cup.portal.com (10/15/90)
>As I recall, the 1620's add and multiply opcodes corresponded to the >character codes for "a" and "m". Maybe some old geezer could confirm >that :-) Sorry, you miss on all three points! A (add) opcode was 21 and M (mul) opcode was 23. A letter was 41 and M letter was 55. And I am only 33, so I'm no old geezer either :-) R. Tim Coslet Usenet: R_Tim_Coslet@cup.portal.com BIX: r.tim_coslet
R_Tim_Coslet@cup.portal.com (10/15/90)
>I've been informed that the opcodes for add and subtract on the 1620 >correspond to the character codes for + and -. I was probably thinking of >the 1401 (or whichever model had an assembler called AUTOCODER). Well, you have been misinformed! + character was 10 and - character was 20. The 21 (add opcode) was a / character and 23 (mul opcode) was , character. The 22 (sub opcode) doesn't correspond to any character. I have the book right infront of me....... R. Tim Coslet Usenet: R_Tim_Coslet@cup.portal.com BIX: r.tim_coslet
gmoff@ccu1.aukuni.ac.nz (Moffat) (10/16/90)
R_Tim_Coslet@cup.portal.com writes:
Ah, I was wondering how a youngster like you had even heard of a 1620 *B^)
--
Graeme Moffat, Phone : +64 9 737 999 x8384
Computer Aided Design Centre, Fax : +64 9 366 0702
School of Engineering, Mail : Private Bag, Auckland, NZ
University of Auckland Email : g.moffat@aukuni.ac.nzjgd@convex.csd.uwm.edu (John G Dobnick) (10/18/90)
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!) 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". yellow card -- IBM 1620, Model 2, Reference card. Form X26-5852-1 record mark -- 0-2-8 punch (C82 in core). Graphic symbol looks like a 'not equal' symbol with a vertical stroke. 1443 lineprinter -- an interesting beast, with an oscillating type bar. Characters were on (removable!) segments and looked like combs - each character was at the end of a spring finger. Switching character segments made for 'interesting' output. (The typebar could also 'let loose' and fly out the end of the machine. :-) Now... does anyone out there remember the IBM 1710 ??? -- John G Dobnick (JGD2) Computing Services Division @ University of Wisconsin - Milwaukee INTERNET: jgd@csd4.csd.uwm.edu ATTnet: (414) 229-5727 UUCP: uunet!uwm!csd4.csd.uwm.edu!jgd "Knowing how things work is the basis for appreciation, and is thus a source of civilized delight." -- William Safire
R_Tim_Coslet@cup.portal.com (10/20/90)
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 BIX: r.tim_coslet