Compaq AlphaServer ES40, Service Manual

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5-12 Compaq AlphaServer ES40 Service Guide
5.2 Fault Detection and Reporting
Table 5–1 provides a summary of the fault detection and correction
components of Compaq AlphaServer ES40 systems.
Generally, PALcode handles exceptions/interrupts as follows:
1. The PALcode determines the cause of the exception/interrupt.
2.
If possible, it corrects the problem and passes control to the operating
system for error notification, reporting, and logging before returning the
system to normal operation.
If PALcode is unable to correct the problem, it
•
Logs double error halt error frames into the flash ROM
•
Logs uncorrectable error logout frames to the DPR
•
For single halts, logs the uncorrectable logout frame into the DPR.
3.
If error/event logging is required, control is passed through the OS
Privileged Architecture Library (PAL) handler. The operating system error
handler logs the error condition into the binary error log. Compaq Analyze
should then diagnose the error to the defective FRU.