Sun Microsystems Ultra 5, Service Manual

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iv Sun Ultra 5 Service Manual • February 2000
3. Power-On Self-Test 3-1
3.1 POST Overview 3-1
3.2 Pre-POST Preparation 3-2
3.2.1 Setting Up a TIP Connection 3-2
3.2.2 Verifying the Baud Rate 3-4
3.3 Initializing POST 3-5
3.4 Maximum and Minimum POST Levels 3-7
3.4.1
diag-level
Variable Set to
max
3-7
3.4.2
diag-level
Variable Set to
min
3-15
3.4.3 POST Progress and Error Reporting 3-19
3.5 Bypassing POST 3-22
3.6 Resetting Variables to Default Settings 3-22
3.7 Initializing Motherboard POST 3-23
4. Troubleshooting Procedures 4-1
4.1 Power-On Failure 4-2
4.2 Video Output Failure 4-3
4.3 Hard Drive or CD-ROM Drive Failure 4-4
4.4 Power Supply Test 4-5
4.5 DIMM Failure 4-7
4.6 OpenBoot PROM On-Board Diagnostics 4-8
4.6.1 Watch-Clock Diagnostic 4-8
4.6.2 Watch-Net and Watch-Net-All Diagnostics 4-8
4.6.3 Probe-IDE Diagnostic 4-10
4.6.4 Test device alias, device path,
-All
Diagnostic 4-10
4.7 OpenBoot Diagnostics 4-12
4.7.1 Starting the OBDiag Menu 4-12
4.7.2 OB Diagnostics 4-16
4.7.2.1 PCI/PCIO Diagnostic 4-17
4.7.2.2 EBus DMA/TCR Registers Diagnostic 4-18