On Mon, May 08, 2000 at 10:01:47PM -0400, Bob Arning wrote:
> On Mon, 8 May 2000 20:41:18 EDT JArchibald at aol.com wrote:
> >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?
> 
> Jerry,
> 
> There were more combinations than that:
> 
> S through Z were 0-1 through 0-9
> 
> some others I *know* were on the keypunch
> 
> period - 12-3-8
> plus - 12-6-8
> comma - 0-3-8
> ampersand - 12
> parens - 12-5-8 and 11-5-8
> 
> Cheers,
> Bob
>

It would be nice if someone with too much time on their hands could
do a PunchCardMorph so we could visualize this a little more directly.

We would also want to have Reader and Punch classes which would 
collaborate with PunchCard and CardDeck. This should be sufficient
to punch out change sets, print them as Postscript, and scan them
into another image through a Reader.

I've always been impressed by the Squeak virtual machine, but I'm
afraid that the virtual I/O has been weak up to this point ;)

Dave