Face down, nine-edge first

JArchibald at aol.com JArchibald at aol.com
Tue May 9 00:41:18 UTC 2000


=> 5/8/00 1:17:50 PM EDT, dnsmith at watson.ibm.com =>
<< It's clearly an enhance, those two extra rows. Question is, who do we 
blame for them? Did Herman Hollerith do it or is it an IBM addition? >>

Hi Dave,

You know, I have been pondering all day the following question, and it has 
been driving me crazy. As Alan pointed out, the standard BCD encoding (Yes, 
my children, there was something before EBCDIC, of which EBCDIC you have only 
heard rumors of) allowed multiple punches only in the 11-row and 12-row 
(There was also a binary card encoding, as has been pointed out, but that was 
quite different from the normal 'keypunch' set). The chararacters '0' through 
''9' had no overpunch (as they were called). The choices of overpunches (an 
11-row, a 12-row, and both 11- and 12- row), gives one 30 more characters. 27 
of these were 'A' through 'Z' (that is where the capital only mentality came 
from) and the space ' ' character.

WHAT WERE THE OTHER 3 CHARACTERS ??? Or have I forgotten some other 
arrangement in the punch card encoding?

Cheers,
Jerry.





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