Sun Microsystems Ultra 1 140 Service Manual page 34

3
3.2 Max and Min Levels of POST
3-2
The second way to start POST is by setting the diag-switch? NVRAM
variable to true and then power cycling the system. To set the diag-
switch? variable to true, type setenv diag-switch? true at the system
ok prompt.
ok setenv diag-switch? true
Turn the power off, wait a few seconds, and then press the power on switch.
This action causes the system to start running the POST diagnostics. While
POST is running, you should see the Caps Lock key on the keyboard flashing
on and off.
When you have finished testing the system using POST, set the
diag-switch? variable back to false (the system's default setting).
ok setenv diag-switch? false
Two levels of POST are available in the system: max (maximum level) and min
(minimum level). The system runs the selected level of POST based on the
setting of the NVRAM variable called diag-level.
The default setting for diag-level is max. In this mode, POST takes about
one minute to run and will send progress and error messages to the system
serial port A. For an example of max POST output on serial port A, see
Section 3.6.1, "Diag-level NVRAM Variable is Set to Max."
When the diag-level variable is set to min, POST takes about 30 seconds to
run and only an abbreviated set of messages and error information are sent to
serial port A. For an example of min POST output on serial port A, see
Section 3.6.2, "Diag-level NVRAM Variable is Set to Min."
To set the diag-level variable to min, at the system's ok prompt type:
ok setenv diag-level min
Sun Ultra 1 Series Service Manual—November 1995