31 Mar
2010
31 Mar
'10
7:32 p.m.
Fred Cisin wrote:
I have one such reader (a Wang C11 Card Programmer), physically kind of like an
old-style side-loading toaster. Sadly, I don't have the calculator it went with.
Hadn't thought of using it for 80-column cards but looking at it I see it
should work as you suggest (but then, I don't have any 80-colummn cards that
need reading, and it would be rather painful for any quantity of them.)
The scanning circuitry is all self-contained, but the scan is not in the normal
column order, it reads 4 bits of 2 sequential columns (8 bits total) at a time.
It should interface directly to a parallel port. Don't know how reliable it
would be though, the contacts are not gold-plated and there is little wipe of
the contacts during the load-unload process.
My other card reader is mechancial (not optical)
and partly home-made. I
got a reading head from some surplus plave. It has 480 (40 columns of 12)
mechancial contacs and a solenoid to lift the card against these
contacts. It reeads half the length of a stanard 80 column card and then
you put the card i nthe other way round to read the other half.
I used to have a Wang card reader. It had 480 contacts, but they were
every other column. It was for "Hanging Chad" port-a-punch type cards. It
was a large clamshell that you manually opened, placed a card in it, and
manually closed. Therefore, it was not for high-volume service-bureau
card deck reading - slightly slower than keying in the data. I had
previously used a Wang desktop programmable calculator that had one. If
you wanted to read a normal 80 column card, you could read the card, turn
it over, and read the other columns, since the margins for IBM cards were
symmetrical. On the Wang calculator, I used an 026, and made "flippy"
cards for some of the more commonly used macros.