EAE Part II

This document outlines "EAE Part II," a diagnostic program for the PDP-9 computer designed to verify the correct operation of its Extended Arithmetic Element (EAE) multiply and divide instructions. The diagnostic is divided into two primary sections, each with distinct testing methodologies and error reporting mechanisms.

Section 1: Set-Up Test This section utilizes pre-determined, fixed numbers to rigorously check various aspects of the EAE. It includes tests for:

• ADVP: Ensuring memory location following an instruction is not modified and the program address counter is correctly incremented.
• NEAE: Verifying the setup of all EAE signed, unsigned, integer, and fraction multiply and divide instructions with a shift count of zero.
• SHCT: Sequentially executing multiply instructions with shift counts from 1 to 22.
• STMUL: Testing all signed multiply and divide instructions.
• MULTST: Employing worst-case number patterns for both EAE and Adder tests.
• MSPEED: Assessing the speed of back-to-back multiply, divide, and mixed multiply/divide operations. Hardware malfunctions detected in Section 1 result in an error halt.

Section 2: Random Data Multiply and Divide Test This section focuses on verifying signed multiply and signed divide instructions using random numbers. It tests these operations at various shift counts (1 through 22 for multiply, 23 for divide) and checks for the proper setting of the LINK bit on divide overflow. The testing sequence involves generating a random number, performing a software operation, then a hardware operation, and finally comparing their results. Malfunctions in Section 2 lead to an error message being typed out on the teleprinter, followed by a processor halt.

The document also specifies system requirements (minimum PDP-9 with EAE, specific memory locations, and subprograms), loading procedures (Hardware Read In at SA=017720), and detailed usage instructions. It explains various AC switch settings that allow users to control error handling (e.g., suppressing error messages, halting after each operation or sequence, repeating tests, or cycling through sections). Furthermore, it provides examples of error typeouts and comprehensive guidance on error recovery, enabling users to repeat specific failed operations, continue testing, or generate detailed simulation printouts to aid in debugging and hardware repair.