"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 <jesse1.robin...@sce.com> 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 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
