PDP-7 Extended Memory Control Test and PDP-7/9 Memory Extension Switch Test

This document describes a diagnostic program (MAINDEC-7A-D1CC-D) designed for the PDP-7 computer. Its main function is to thoroughly check the extended memory control logic and verify the proper operation of various instructions within each available bank of extended memory. Additionally, an optional test is included for systems equipped with the PDP-7/9 memory extension switch.

The document provides detailed instructions for users, covering system requirements (a standard PDP-7 or PDP-7A with at least 12K of core storage), the loading procedure for the object tape, and operational guidance for running the tests. It explains how program passes are indicated (by a Teletype bell ring) and how hardware failures are reported via error halts. The tests are designed to run continuously and repeat 4096 times for each routine, with provisions for user control via AC switches for single-routine execution or continuous looping to aid in troubleshooting intermittent errors. A comprehensive list of error halts and their descriptions is provided for both the extended memory control test and the optional memory extension switch test.