Virtual IBM Punch Card Data Processing

Simulates operating a keypunch a.k.a. cardpunch machine. May be configured as an IBM026, IBM026-H, or (default) IBM029. The commandline option -r selects the IBM026 configuration. The option -H selects the IBM026 character set "H" (typically used for FORTRAN).

Output from this program may be used as input to the Honeywell 200/2000 Series Computer as well as future Punch Card Data Processing simulations. Note that the Honeywell 200/2000 Series punch card equipment was based on the IBM 026-H character set (48 characters) plus Honeywell extensions to add 16 characters. There is evidence of a Honeywell-branded (OEM'ed) IBM 029 card punch machine, however no information exists on this model and it's character set. Here is more information on keypunch character sets.

Card decks punched by other programs can also be viewed here, using the IBM 029 "interpret" feature to print column characters as needed. The punch card data carries information about which columns were printed (had the printer enabled when punched or interpretted), and this program uses that data to show (or hide) the column interpretation. Note that printing here is not identical to original keypunch equipment. On the original hardware, multipunches or re-punches would cause multiple, overlapping, characters to be printed. This program only prints once, based on the current punches. If the final (current) column punches do not represent a valid character, nothing is printed.

Basic help is included.

Additional punch-card data processing equipment is under development. The application DataCenter.jar provides central access to all punch card equipment simulations. See also the examples.

Downloads are available at

Contact: durgadas311@gmail

The story of the purple ink: As I recall, IBM Keypunch machines (at least the 026) used the same ribbon as some other popular office equipment. So, rather than buy IBM-branded ribbons, many sites would use something else. My high school used some brand of adding-machine ribbons, that came in a purple-blue ink, for their IBM 026's. In memory of that, I have also chosen that color ink for this simulation - when in IBM 026 mode.