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Here is how zoned and signed numbers came to be the same: A number was a single punch, but a zone punch with it made it a minus number. >From http://www.cs.uiowa.edu/~jones/cards/codes.html : "The original punched card coding used by Hollerith allowed coding of only a limited alphabet; over the years, this was extended in many ways, but while many of these extensions were upward compatable from the original code, no attempt to standardize the extensions was successful until the end of the punched card era. As a result, keypunch users got quite used to learning, for example, that ¢ was to be typed when [ was intended. The standard punched card had 80 columns, numbered 1 to 80 from left to right. Each column could hold one character, encoded as some combination of punches in the 12 rows of the card. Rows were numbered and grouped as follows: ____________ / / 12 / O Zone rows 11| O \/ 0| O / 1| O / 2| O / 3| O Numerc 4| O rows 5| O \ 6| O \ 7| O \ 8| O \ 9| O |______________ There is some ambiguity in the classification and numbering of the 10th row. This was either numeric row 0, because it was usually punched to encode the numeral zero, or it was zone row 10, because it served to mark one of the three "zones" into which the alphabet was divided. Punches in rows 8 and 9 also identified distinct zones in some card codes, although they were not usually described as such. In written material on card codes, hyphenation was used to connect the row numbers punched in one column to encode one character; for example, in most card codes, a comma was encoded as 0-8-3, or punches in rows 0, 8 and 3 of one card column. In this notation, zone punches were always listed first, and for the triple punch characters involving row 8, this was usually listed between the zone punch and the numeric punch that distinguished that character. " --------------------------------------------------------- Booth Martin http://www.MartinVT.com Booth@MartinVT.com --------------------------------------------------------- -------Original Message------- From: midrange-l@midrange.com Date: Friday, November 29, 2002 01:46:59 PM To: midrange-l@midrange.com Subject: Re: Odd/Even packed numbers. Barbara, >Thanks Doug, that does explain it somewhat. It gives a reason if not an >excuse. And it may not be the real reason -- it is just my lame justification for how it may have ended up using S. Doug _______________________________________________ This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list To post a message email: MIDRANGE-L@midrange.com To subscribe, unsubscribe, or change list options, visit: http://lists.midrange.com/cgi-bin/listinfo/midrange-l or email: MIDRANGE-L-request@midrange.com Before posting, please take a moment to review the archives at http://archive.midrange.com/midrange-l. .
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