2–4
DECbridge 500/600 Problem Solving
•
The five FRU_BAD indicators will be off (one for each logic module and one
for the fan assembly), indicating that no FRU failures were detected.
•
The following indicators will be on (solid green):
–
MODE indicates that self-test is complete.
–
DC_OK indicates that the power supply is OK.
–
EXT_PWR indicates that the AUI transceiver power is OK.
–
After approximately 30 seconds, the FWD indicator will turn on for each
port ready to forward packets. (If a port is in BACKUP state, that port’s
FWD indicator remains off.)
•
The PHY_1 indicator (and PHY_2 on DAS models) will blink (green) until
the fiber interface connection is complete, then turn on (solid green). (This
assumes that the bridge is properly connected to the FDDI network.)
•
On any DECbridge 500 series unit, the AUI_SELECT indicator will be on
(solid green) if the bridge uses the AUI connection to the network, and off if
the bridge uses the ThinWire connection. (Configuration switch 8 in the ON
position selects the AUI interface, and in the OFF position selects the Thin-
Wire interface.)
•
All ACT indicators can be on (yellow), off, or flashing as packets are trans-
mitted and received over each network segment.
If the bridge is not operational, the MODE indicator will remain off and one or more
of the FRU fault indicators (AP_BAD, QM_BAD, and so on.) will be on.
2.3 Self-Test Diagnostics (Overview)
The ROM-based self-test diagnostics used by the DECbridge 500/600 series consist
of a core test followed by a series of more extensive tests to check each of the four
logic modules in the bridge.
The core test verifies that the hardware needed to run the diagnostics is functioning
properly. This core test checks the microprocessor and associated address decode
and bus control, the AP bus, and some of the AP or AP2 module memory, including a
CRC test of the code in the EPROM and EEPROM.
