Digital Equipment DEC 3000 Series Service Information page 257

LED Codes,
Memory LED
Codes
Continued
The following LED codes represent memory diagnostic tests. If an
error occurs during one of these tests, the screen displays an FRU
code and error code.
All values are in hexadecimal.
LED Code
20
21
22
23
24
25
26 to 2a
2b
2c
2d
2e
2f
Description
Machine check
CELL Fill mem with test pattern data
CELL Forward Rd/Compare/Complement/Wr
CELL Reverse Rd/Compare/Complement/Wr
ADDR Fill mem with addresses as data
ADDR Read/Compare data = address
Reserved
LLSC load-locked/store-conditional tests
BCTP Bcache Tag Parity detection
ECC detection
Reserved
Clear memory to zeros
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