Maintenance and Service Guide 5-31
Addendum 108431-001 (11-88) to
Manual No. 108033-003
5.4 MEMORY ERROR CODES
Memory error codes appear when the system
detects a memory fault during the Power-On
Self-Test (201 or 203 error codes) or as a result
of a diagnostic test (203 error codes). The TEST
programs attempt to isolate the memory fault to
a specific location, then generate a memory error
code that identifies the defective system memory
board or system memory module to be replaced.
The memory error code points to a specific
memory address. The physical location of the
memory address depends on the number and
type of memory boards installed and the type of
memory device used.
The first one megabyte of RAM in the system is
mapped into various areas of the system memory
map. The common configuration is that the
first 640 Kbytes are the base memory. The next
256 Kbytes are used by the COMPAQ Expanded
Memory Management (CEMM) Program. The
last 128 Kbytes are reserved for system use. The
base memory size is configured on the system
memory board to 256 Kbytes, 512 Kbytes, or
640 Kbytes. When the base memory size is
reduced, the RAM normally assigned to the base
memory is mapped into the extended memory
space.
To Next Page
Loading...
