COMTRAN Reconstruction

J28-6169 · January 1962

02.08.02

PDF page 67 of 221. Download the scanned PDF

The page as scanned

The scan of PDF page 67 of J28-6169
Select the scan to open it at full size.

The text read off it

[02.08.02]

  1. The following pseudo ops may not be used:

    HEAD
VFD
DEC
DUP
ORG
SYN
END

  2. Literals are not presently permitted in machine language.

C. Flexibility Above that of SCAT

In using the CRYPT language, advantage may be taken of several Commercial Translator features which have been added to SCAT facilities:

  1. Names which are defined in the Commercial Translator sections of the program may be referenced in the variable field of the machine language sections. Thus, names in the variable field may contain up to 30 characters. Compound names (qualified) may not, however, be used in the machine language section. If such a qualified name is to be used, it should be renamed as a single name, using the CALL verb outside a CRYPT section.

  2. The Commercial Translator system for the 709/7090 addresses array elements by the use of "Symbolic Registers". The Symbolic Register for the array, A(I,J), always contains the address of the element corresponding to the present values of the component variables, I and J. The system will replace a symbolic instruction of the form CLA A(I,J) with the following instruction: CLA* SRAIJ. It should be noted that the system will not check for changes in component variables while in the machine language mode. Therefore, although the programmer may change the values of I or J, the Symbolic Register for A(I,J) will not be updated by the System. Also, indirect addressing is not permitted on the original operation.

  3. Arithmetic expressions may contain parenthesis. For example, the following is a legitimate usage: AXT A*(B + C),4.

  4. The Commercial Translator Data Description form provides a flexible and effective means of describing data and entering constants.