If "S" was assigned the 0 and 2 rows because 0 and 1 were too close together, then why was "/" given rows 0 and 1? Does that punch a hole in this theory? GD&R
Bill On Tue, 2 Jun 2020 14:30:52 -0700, Charles Mills wrote: >"Laced" (every hold punched) cards were an amusing bulletin board item. > >And yes, I believe I heard at the time @Jesse's premise as to why 'S' did not >use row 1. > >Actually, the alpha codes are as follow: > >A - I, row 12 plus rows 1 - 9 >J - R, row 11 plus rows 1 - 9 >S - Z, row 0 plus rows 2 - 9 > >So you see that if S used row 1 it would have had two adjacent rows punched, 0 >and 1. > >(The rows, from top to bottom, are 12, 11, 0 - 9.) > >Non-alphanumeric punches were fairly rare, and column binary was extremely >rare. > >Object code decks of course contained non-alphanumeric punches. The X'02' that >begins each (traditional) object code record, preceding ESD, TXT, RLD or END? >I still think of it as "12-2-9.") > >Charles > > >-----Original Message----- >From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On >Behalf Of Steve Smith >Sent: Tuesday, June 2, 2020 2:07 PM >To: IBM-MAIN@LISTSERV.UA.EDU >Subject: Re: Punched cards and character set > >That's plausible, I think. While there are plenty of adjacent punches in >the full 256-characters, I'm sure most cards were mostly alphanumeric only, >and it might pay to make them as strong as possible. I remember seeing >some cards that were punched in every position; those were very delicate, >and definitely couldn't survive a pass through a card reader, regardless of >the fact they had no validity at all. > >sas > >On Tue, Jun 2, 2020 at 4:55 PM Jesse 1 Robinson >wrote: > >> I haven't seen this mentioned. The punch card codes for letters went like >> this: >> >> A - I rows 1 - 9 >> J - R rows 1 - 9 >> S - Z rows 2 - 9 >> >> So why was S assigned to row 2 instead of row 1? The answer I was taught >> was that row 1 was too close to an adjacent location. The punching/reading >> devices and card stock of the day could not reliably handle punches that >> close together, so row 1 was skipped for the third alphabetic sequence. >> >> What's amusing is that this pattern was carried over to EBCDIC. The code >> for S likewise skips a possible combination: D9 to E2; 'E1' is not assigned >> to an alphabetic character. >> >> > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
