Control Cards

Part of the Punched Card Collection
by Douglas W. Jones
THE UNIVERSITY OF IOWA Department of Computer Science

Each deck of punched cards submitted to a computer center described one job for the computer to do. The deck might contain many sub-sections, perhaps a source program, perhaps an executable in binary format, and possibly one or more blocks of data to be input to the program. The entire deck would typically be headed by a job card, and each subsection would be introduced by one or more control cards.

Today, we speak of command-line interpreters such as the various Unix shells or Microsoft 's COMMAND.COM and its successors. IBM's 360 and 370 series of machines supported JCL, IBM's Job Control Language, and similar command languages existed for most computers. When input was from punched cards, the control cards held commands in the appropriate command language.

Many computer users simply punched command-language control cards on the same cardstock used for other material, but it was useful to punch them on a different color of stock in order to make it easy to separate programs or data from the cards that "glued" them together into a job.

Hummel 5477
Brown Boveri
Leibnitz Rechenzentrum München
Thyssen AG

Click on any image for a high-resolution version. All images were scanned at 600 dpi and edited to remove streaks caused by bad (or dust occluded) pixels in the scanner. Note that, prior to 1978, all material printed in the US without a copyright notice was automatically in the public domain; this also applies to most material printed before 1989 without a notice. Beware, however, that institutional logos are typically protected by trademark law and cannot be used in a manner that conflicts with the trademark owner's rights.

Hummel 5477

Hummel was a major card supplier in Germany. This Steuerkarte or control card, was among their offerings. Aside from the notation Steuerkarte, nothing about the design of this card is specific to its use for holding a line of some command language.

Note that Steuerkarte could also be translated "tax card," but that the German word Steuer has many other connotations related to control or steering.

Brown Boveri

Brown Bovari had both sides of this card printed. The other side was an OS/360-style Job card. The side shown here is contains formats for two different IBM JCL statements, the EXEC (execute) statement and the DD (data definition) statement. The comparable card printed for Thyssen AG contained layout guidelines for a much wider variety of JCL statements.

Leibnitz Rechenzentrum München

The Leibnitz Rechenzentrum (computer center) in Munich is known today as the Leibnitz Supercomputing Centre, a branch of the Bavarian Academy of Sciences and Humanities. This command card is from the 1970s, when they used a TR 440 mainframe; TR stands for Telefunken Rechner (computer).

Thyssen AG

This job control card from Thyssen AG has a marginal date of 10/79 in the upper right. Thyssen's corporate logo on this card is far smaller than necessary. The card itself is formatted for a number of different commands for the IBM System 360/370 Job Control Language. The topmost line on the card explains the initial format of a job card, while the other lines give guidance for the formats of other commands. The comparable card printed for Brown Bovari contained layout guidelines for only the two most common JCL statements.

This is one of the few job cards in the collection that suggests using the same color of card for both the job card and other cards that might be scattered through the card deck of a job.