Specifications

When the SCU executes, it is able to detect automatically the system board
configuration (CPUs and memory) and any EISA modules that are installed.
EISA modules are detected by polling modules on the EISA bus. ISA modules
are detected by the use of ISA CFG files; you define the ISA modules installed
in the system.
The SCU then creates a system configuration file which represents the
configuration of the system. The SCU saves system configuration files in two
ways:
• By writing system configuration data to nonvolatile memory on the system
board
• By writing a system configuration file to the system configuration diskette
The stored data is accessed by the system firmware and must be accurate.
Therefore the SCU must be run whenever the system configuration changes.
The system configuration file is also written to the SCU diskette as a backup.
The file is included on the system as an SCI file.
Note
The SCU diskette must be write-enabled to write a system
configuration file to the diskette. No error message is produced if
the SCU is able to write to memory but not to the diskette. You must
ensure that the SCU diskette is write-enabled.
5.2.1 Diskettes Provided
Two configuration diskettes are provided for use with the applicationDEC 400xP
system, the SCU diskette and the library diskette. The SCU diskette contains
both the SCU program and the system configuration files. When the SCU
prompts you for the "System Configuration Diskette," this is the diskette that
is needed. Also provided is a library diskette, labeled "Library Diskette," which
contains ISA CFG files for many ISA modules.
5–2 System Configuration