MS650-AF/BF/BH/BJ MOS Memory Option

This document is an Installation Guide for the Digital Equipment Corporation MS650-AF/PF/BH/BJ MOS Memory Options in BA200/BA430 series microsystem enclosures.

Key aspects covered:

• Memory Options: Details four types of MS650 memory modules (8MB, 16MB, and 32MB) designed for BA200/BA430 enclosures, specifying their part numbers and system compatibility (e.g., MicroVAX 3300/3400, 3500/3600, 3800/3900, VAX4000-200, DECsystem 5400).
• Intended Audience: Primarily qualified self-maintenance customers with a microsystems maintenance kit, or Digital Services personnel.
• Critical Safety and Installation Precautions: Emphasizes the necessity of wearing an antistatic wrist strap and ensuring bus grant continuity (no empty backplane slots between modules).

• Configuration Rules:

  • Maximum system memory supported is 64 MBytes.
  • A "board equivalent" rule exists, limiting total system memory to 4 board equivalents (e.g., KA640 CPU is 1, 8/16MB modules are 1, 32MB module is 2).
  • Module placement rules: memory modules must be installed in contiguous slots directly adjacent to the CPU module. The 32MByte MS650-BC/BJ module must be installed furthest from the CPU.

• Installation Process: Provides step-by-step instructions including:

  • Unpacking and inspecting the kit contents.
  • Performing software backup and system shutdown.
  • Testing the existing system.
  • Checking and configuring the existing setup and the new MS650 module (no jumpers/switches on the module).
  • Relocating existing modules if necessary (procedures for modules with blank covers and handles).
  • Installing the new MS650 module and connecting the CPU/Memory Interconnect Cable.
  • Verifying ground connections, including the use of gap filler assemblies for EMI compliance between certain module types.
  • Reconnecting external devices and system covers.

• Installation Verification: Outlines steps to confirm successful installation, such as power-on self-tests, MDM diagnostics, and using SHOW MEMORY commands at the console and in VMS.

• FRU (Field Replaceable Unit) Isolation: A dedicated section explains that the 32MByte MS650-BC/BJ module appears to the system as two 16MByte modules, which can lead to misleading diagnostic reports. It provides a "Bank-To-Module Translation" table and examples to correctly identify the physical module in case of an error report.