Compaq ES40CSLP, Инструкция по установке, использованию и обслуживанию

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Troubleshooting and Diagnostics
6–52 Compaq ES40CSLP Rackmount System Installation/User/Service Guide
6.7.3 Fault Detection and Reporting
Table 6-10 provides a summary of the fault detection and correction components of Compaq
ES40CSLP systems.
Generally, PALcode handles exceptions as follows:
1. The PALcode determines the cause of the exception.
2. If possible, it corrects the problem and passes control to the operating system for reporting
before returning the system to normal operation.
If PALcode is unable to correct the problem, it
– Logs double error halts into the flash ROM
– Logs uncorrectable errors to the shared RAM
– For single halts, logs the uncorrectable logout frame into shared RAM.
3. If error/event logging is required, control is passed through the system control block (SCB)
to the appropriate operating system exception handler. The operating system exception
handler logs the error condition into the binary error log. If the error is not an uncorrectable
CPU error or system error, Compaq Analyze should diagnose the error to the defective
FRU.
Table 6-10 Compaq ES40CSLP Fault Detection and Correction
Component Fault Detection/Correction Capability
Alpha 21264 microprocessor
Contains error checking and correction (ECC) logic for
data cycles. Check bits are associated with all data entering
and exiting the microprocessor.
A single-bit error on any of the four longwords being read
can be corrected (per cycle). A double-bit error on any of
the four longwords being read can be detected (per cycle).
Backup cache (B-cache) ECC check bits on the data store, and parity on the tag
address store and tag control store.
Memory DIMMs ECC logic protects data by detecting and correcting data
cycle errors. A single-bit error on any of the four
longwords can be corrected (per cycle). A double-bit error
on any of the four longwords being read can be detected
(per cycle).
PCI SCSI controller adapter SCSI data parity is generated.
ISA-to-PCI bridge chip PCI data parity is generated.