M-1125 Aug61

This document is a Permanent Memorandum (M 1125) from Digital Equipment Corporation, dated August 29, 1961.

The memo describes a Multiply Step and Divide Step Test Program for the PDP computer.

Purpose: The program is designed to test the multiply step and divide step instructions of the computer.

How it Works:

1. A test number is input by the user via the test word switches and stored in memory.
2. This number is then multiplied by itself.
3. The resulting product is divided by the original test number.
4. The outcome of the division is compared against the original test number.
5. If no error is found, the program continuously loops.
6. If an error is detected during the comparison, the program will halt at location 1066.

Operating Instructions:

1. Load the test tape with all sense switches down.
2. Input the desired test number using the test word switches, set the starting address to 1000, and press the start button.
3. To test with a different number, stop the program, input the new number via the switches, and press start again.