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System Troubleshooting and Diagnostics
5.2 Product Fault Management and Symptom-Directed Diagnosis
Uncorrectable ECC memory error entries include a Memory subpacket
(Figure 5–4). The memory subpacket consists of MEMCON, which is a
software register containing the memory configuration and error status used
for FRU isolation, and MEMCONn, the hardware register that matched the
error address in MEAR.
Figure 5–4 Memory Subpacket for ECC Memory Errors
3 1
0 0
0.
4.
MEMCON
MEMCONn (one longword from 2101.8000 - 2101.801C)
MLO-007266
Correctable Memory Error entries have a Memory (Single-Bit Error) SBE
Reduction subpacket (Figure 5–5). This subpacket, unlike all others, is of
variable length. It consists solely of software registers from state maintained
by the error handler, as well as hardware state transformed into a more usable
format.
Figure 5–5 Memory SBE Reduction Subpacket (Correctable Memory Errors)
3 1
0 0
Memory SBE Reduction Subpacket
CRD Entry Subpacket Header
CRD Entry #1
CRD Entry #2
.
.
.
CRD Entry n
Max n = 16
MLO-007267
The OpenVMS error handler maintains a Correctable Read Data (CRD)
buffer internally within memory that is flushed asynchronously for high-level
events to the error log file. The CRD buffer and resultant error log entry are
maintained and organized as follows:
5–12 System Troubleshooting and Diagnostics