Sun Microsystems SunSwift SPARCserver 1000, Service Manual

Page: 42 / 218

2-2 SPARCserver 1000 System Service Manual—June 1996
2
The last column lists indicators used to verify system operation.
Table 2-1 Hardware and Software Control of the System
Control Area Actions Observations Indicators
AC input With the AC power switch (system
rear) on and the key switch in
(Standby), AC (via the fan tray) is
applied to the DC power supply. Listen to hear the fans. The left green LED (front
panel) should light denoting
the power supply is
delivering DC.
Control
board The control board maintains the
system in reset until all DC supplies
reach nominal operating voltage.
Buffers on the control board pass
status signals from the power supply
and fan tray to the system board. The control board has eight
LEDs: the four yellow (left side)
denote system status; the four
green (right side) denote power
supply status. All green LEDs should be on
All yellow LEDs should be
off.
System
board The system monitors AC voltage, DC
voltages, fan rotation speed, and
system board temperature. The system
will shut down the power supply if
monitored conditions fail to reach or
to maintain nominal range.
POST Each system board runs POST
individually. Then POST tests the
ability of system boards to work
together on the backplane.
POST does not test individual SBus
cards, drives, or interface cables.
POST next configures the system,
omitting marginal or failing circuits.
The system master is assigned to be
the first functional system board (with
at least one SPARC module) residing
in the lowest card cage slot. This is
often (but not always) slot 0.
POST
• displays error messages on a
terminal (if connected)
• displays LED codes on
system boards (note: POST may
reset the SPARC processors and
LED codes may be lost) POST cycles the middle
(yellow) front panel LED —
denoting tests are running.
After about 60 seconds, the
yellow LED turns off and the
two green LEDs light; any
other combination of LEDs
denotes a minor or major
problem. If the problem is
• minor, system boot
initiates (all three
LEDs lit)
• major, the system cannot
run and the right side
green LED remains off