IBM 029 Card Punch and ASCII Machines

Johnny Billquist bqt at
Sun May 10 05:18:12 CDT 2015

On 2015-05-10 10:56, Robert Jarratt wrote:
> I recall back in the late 70s using an IBM 029 Card Punch to punch cards for
> the DECSYSTEM-20.
> As I understand it, the 029 was an EBCDIC machine, but of course the
> Does that mean there was an ASCII version of the 029, or that there was
> something in the card reader software on TOPS-20 that converted EBCDIC to

Punched cards are actually not EBCDIC. Nor are they ASCII.
That said, yes, the card reader driver needs to translate the card 
encoding into ASCII when reading cards.


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