Normal Mode; Full Diagnostic Mode - Sun Microsystems SPARCstation 5 Service Manual

If the system passes all the POSTs, all four LEDs light again and then go off. Next,
the OBP firmware performs its initialization sequence and the system banner appears
on the screen. A generic SPARCstation banner is shown as an example. From this
point on, the keyboard LEDs assume their normal functions (that is, you should no
longer interpret the LEDs as diagnostic error indicators).
Figure 3–4 SPARCstation System Banner
Following the system's successful initialization, the operating system is booted
automatically—unless the NVRAM configuration options specify otherwise.
You can retrieve more detailed POST failure information by connecting a terminal to
the ttya serial port. If you connect a terminal, you must set the NVRAM parameter
diag-switch? to true. For more information about the NVRAM parameters, see
Table 2–1. Test failure messages are displayed on the system monitor or console,
whether or not the system is in Diagnostic Mode. However, it may be easier to
understand the failure message output when it is accompanied by more detailed
POST progress messages available via the ttya serial port.

Normal Mode

Under Normal Mode, when the system is turned on, control is sent to the OpenBoot
PROM. Depending on the options set in the OpenBoot PROM, for example if
auto-boot? is enabled (set to true), the operating system will load. Diagnostic
testing is not run.

Full Diagnostic Mode

Full Diagnostic Mode tests the major hardware system board components and, if the
POST is successful, control is transferred to the OBP firmware that probes the
installed SBus modules. Full Diagnostic Mode runs if one of these conditions is met:
4 You press and hold the Stop-d keys while you turn on the power.
4 You set the diag-switch? NVRAM parameter to true in the OpenBoot PROM.
SPARCstation 5 Service Manual ♦ Revision A, August 1994
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