M200 interfacing

From: Frank McConnell <fmc_at_reanimators.org>
Date: Sat Dec 28 23:25:00 2002

Sellam Ismail <foo_at_siconic.com> wrote:
> Whether this will work depends on how punch card encoding works. From
> what I can tell so far, there will only ever be one of the 1-9 numbered
> rows punched per column, but there can be any combination of the 0, 11,
> and 12 rows. Is this correct?

No. Symbol characters do not follow this rule, for example the period
character '.' is encoded as punches in rows 12, 3, and 8.

You should assume that any combination of rows may be punched. As a
general rule, I think you'll find that for cards containing printable
characters, no more than 3 punches are made in any column, but I don't
think you can assume this for cards containing binary data.

Doug Jones has a page that you should look at:
...but I can't get there right now, so you might need to look in
Google's cache (long URL w/wrap):

-Frank McConnell
Received on Sat Dec 28 2002 - 23:25:00 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:34:41 BST