Instruction Test 1

This document outlines a diagnostic program designed specifically for the PDP-8I computer to test its AND, TAD, and OPERATE instructions.

Key details of the document include:

• Objective: To verify the functional integrity of specific processor instructions on the PDP-8I.
• Requirements: A PDP-8I computer with a Teletype. The program occupies memory locations 0000–4354.
• Operating Procedure: The program uses the standard binary loader for setup. The operator must set the switch register (SR) to 7777, load the starting address of 0144, and then run the program. It executes at a rate of 13 loops per second, and the Teletype bell rings after every 128 loops.
• Error Handling: If an error occurs, the program halts with a non-zero AC. Operators can replace specific instructions with a JMP to loop on a test causing an error to facilitate troubleshooting.

• Testing Sequence: The diagnostics are performed in the following order:

  1. Operate instructions (excluding rotates)
  2. TAD instructions
  3. ROTATE functions
  4. Group 1 operate instruction combinations
  5. Group 2 operate instruction combinations
  6. AND instructions

• Miscellaneous: The document includes a complete assembly listing and a symbol table for the diagnostic code.