B–2
Troubleshooting
B.3 Troubleshooting Systems that Include a PMC I/O Companion
Card
A problem in the PMC I/O companion card that hangs the PCI bus signal lines
could cause diagnostics to report problems throughout the I/O subsystem and in
the PCI controller of the processor chip. If you have a PMC I/O companion card
installed and you are experiencing diagnostic failures, remove it and rerun the
POST diagnostics.
B.4 Operating System and Application Use of the Dot Matrix
Display
Operating system and application software can use the dot matrix display. Once
the system boots, the dot matrix display is no longer under control of the console
code and can change. The console automatically clears the display before booting
an image.
B.5 Troubleshooting Your SBC
Table B–1 lists symptoms and corrective actions you can use to troubleshoot
Alpha VME 5/352 and 5/480 SBCs. See the Alpha VME 5/353 and 5/480 Single-
Board Computers User Manual for more information on system diagnostics.
Table B–1 Troubleshooting Your SBC
Symptom
Corrective Action
No LEDs are lit and a prompt does not
appear on the console.
Check the power source. If 5 V power is
out of specification, the SBC is held in
reset. Check that all modules are seated
properly.
The green LED is lit and the number 4
appears on the dot matrix display when you
power on the system.
Check the seating of the memory modules.
The green LED is lit and the number 0
appears on the dot matrix display when you
power on the system.
Ensure that the console terminal is not in
“hold screen” mode.
The green LED is lit and a flashing A
appears on the dot matrix display when you
power on the system.
Check the SCSI termination, the seating of
the Alpha VME 5/352 and 5/480 SBC CPU
and I/O module assembly, the seating of the
breakout modules, the seating of the SCSI
cable, and the seating of all SCSI devices.
The green LED is lit and a flashing D
appears on the dot matrix display when you
power on the system.
Check that the TOY Clock/NVRAM
device is seated properly.
The green LED is lit and a flashing F
appears on the dot matrix display when you
power on the system.
Check the seating of the network address
ROM.
The green LED is lit and a flashing G
appears on the dot matrix display when you
power on the system.
Check the seating of the twisted-pair cable
and the nearest network transceiver.