Research and Advances

Mark sense and port-a-punch programming inputs

The United States Military Academy is faced with the situation whereby 700 cadets may in a single subject prepare computer programs in class one day and get their solutions in the form of a computer runoff at their next class attendance. If the programs had to be processed by conventional keypunch techniques the peak requirements for keypunching would be overwhelming. Keypunched cards with operator errors caused by misinterpreted coding sheets could not be returned to students for review and correction prior to the time the solutions are required in class. This situation has caused the Military Academy to investigate methods bypassing the keypunching operation. A number of special type mark-sense and Port-A-Punch cards have been used. Figure 1 shows a card used with SADSAC, a simplified academic design single address computer; Figure 2, a card for SASSY, a symbolic assembly program; Figure 3, a card for CADETRAN, a dialect of FORTRAN. (It contains the arithmetic statement X = 3.5 * A/(K**2 - C**2).) The CADETRAN/FORTRAN card is printed in four colors. Numbers (which require marking of a single position) are printed in black. Letters of the first third of the alphabet are printed in green, as is the 12-zone position which is identified A→I. Middle third letters of the alphabet are printed in red, as is the 11-zone position identified J→R. The final third of the alphabet is printed in blue as is the 0-zone position, and identified as S→Z. Commonly used symbols which would require 3 marks have been brought out to a separate left column where a single mark serves to identify them. Common but lengthy verbs such as FORMAT, DIMENSION and READ may also be represented by a single mark.


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