DEC-10-CKRMA-A-D CHK11 Reference Manual Apr76

This reference manual, published by Digital Equipment Corporation in April 1976, details the CHK11 hardware test software. It is designed for individuals responsible for loading PDP-11 communications systems (such as DAS44, DAS78, DN80, DN81, DN82, DN85, and DN87) and provides the necessary information to interpret the output displayed by CHK11.

CHK11's primary purpose is to perform an initial hardware survey during system startup, ensuring that the system's devices and memory are functioning correctly by checking for common problems.

Key aspects and functionalities of CHK11 include:

• System Initialization: Upon startup, it identifies and prints the names and quantities of devices present in the system.
• Error Reporting: Errors are typically displayed on the PDP-11's console terminal (CTY). If no CTY is present, errors are indicated by stop codes on the console data lights.

• Detailed Error Messages: When a problem is detected, CHK11 provides a structured error message including:

  • Device name, number, and address.
  • The program counter (PC) listing address where the error occurred.
  • A message describing the problem (e.g., "BIT DID NOT CLEAR", "INTERRUPTED TO WRONG VECTOR").
  • The register/address in question.
  • The expected value (GD), the received value (BD), and an exclusive OR (XOR) value highlighting the differing bits.

• Types of Tests Performed:

  • Bit Clear and Set Test: Verifies that read/write bits in device registers can be properly cleared and set.
  • Interrupt Test: Ensures devices interrupt correctly at the appropriate vector address and Processor Interrupt (PI) level, and do not interrupt when disabled.
  • Memory Test: Checks the read/write functionality of all bits in core memory; memory errors are considered fatal.
  • DL10 Base Address Determination: Locates a suitable base address for the DL10 device.

• Fatal Errors and Stop Codes: Certain critical issues (e.g., memory errors, KW11 problems, bus errors) result in a "FATAL ERROR," causing CHK11 to halt and display a specific stop code on the console data lights (e.g., 1 for bus error, 6 for memory error).

• User Interaction: For non-fatal errors, CHK11 prompts the user whether to proceed. Users can choose to continue, even if the system might be partially functional.

The manual then dedicates extensive sections to listing and explaining specific error messages associated with various PDP-11 devices (e.g., CR11, DH11, DL10, DM11BB, DN11, DQ11, DS11, KG11, KW11, LP11, MM-11, PA611, PP11, PR11, TC11), referencing the core test descriptions where applicable.