Power-On Self-Test (Post) - Sun Microsystems SPARCclassic Service Manual

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CHAPTER

Power-On Self-Test (POST)

This chapter describes the Power-On Self-Test (POST) for normal, full, and
abbreviated modes, available with your SPARCclassic and SPARCstation LX.
4 "Power-On Self-Test (POST)" on page 21
4 "Normal Mode" on page 23
4 "Full Diagnostic Mode" on page 24
4 "Abbreviated Diagnostic Mode" on page 24
4 "Tests the POST Runs" on page 25
4 "POST Error Messages" on page 28
4 "Status Lights (LEDs) and Indicators" on page 29
The Power-On Self-Test (POST) diagnostics reside in the Open Boot PROM located
on the system board. There are two POST modes: Normal and Diagnostic.
Power-On Self-Test (POST)
The Power-On Self-Test (POST) runs when you turn on the system unit power switch
and any of the following conditions apply:
4 Keyboard is disconnected.
4 Stop-d keys are held down when you turn on the power.
4 diag-switch? NVRAM parameter is set to true.
The POST comprises a sequence of tests designed to evaluate the major hardware
components of the main logic board in the short time before the operating system is
booted. The POST does not perform extensive testing on any component of the main
logic board. Only major failures can be detected by the POST.
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