Instruction - Data Storage
Storage of data and instructions in the same half of a register. A technique has been
developed which allows the storage of both a number and program instructions in the same
half of a register (F, f, E, e, D, d).
This technique permits the programmer to address a register having both a number and
instructions in it, and perform any transfer, arithmetic, print or clear operation with the
number - without disturbing the instructions in that register and without getting an error light.
The number, which may be either a constant or accumulation, must precede the instructions
and must not exceed the space allotted for it. For this purpose, the registers should be
considered as 24 digit registers with the upper half (F, E, D) containing positions 1-12 and the
lower half (f, e, d) containing positions 13-24. A two digit number in the upper half of a
register would thus occupy positions 1 and 2. A two digit number in the lower half would
occupy positions 13 and 14.
The procedure for storing both program instructions and a number in the same half of a
register (F, f, E, e, D, d) is as follows:
1.
Instructions are keyed into the computer in the usual manner, except that if it is decided to
use a portion of a half-register for the storage of a constant or an accumulation, an S
should be entered in the program for each digit in the constant or anticipated
accumulation.
2.
To use the LOWER HALF of a register (f, e, d) in this manner there must be a 'signal stop'
(an S) in the
12th position
of the register concerned (see Fig. 1).
To use the UPPER HALF of a register (F, E, D) in this manner there must be a 'signal stop'
(an S) in the
24th position
of the register concerned (see Fig. 2).
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