LED Summary
LED1Off On Flashing
Power No Power Power OK
Module OK Self-test failed Self-test OK
or not operating
4/16 Mb/s No activity Valid speed or
management set
speed
Lobe Inactive Connected to network Continuous single flash: network
management disabled port.
Continuous double flash: wrong speed.
Hub MAU ONLY:
Ring A/B Not connected Connected to Ring A Continuous single flash: network
or Ring B management disabled port.
A and B alternately flash: MAU needs an
upgrade or an upgrade is in progress.
DEChub ONE ONLY:
Ring In/ Inactive or Connected to network Continuous single flash: network
Ring Out wire fault management disabled port.
Continuous double flash: wrong speed.
1 Scroll: During power-up self-tests, all LEDs, except the Power LED, indicate a scrolling
pattern.
The LEDs indicate status by being on, off, and flashing. Flashing LEDs indicate special situations.
There are two flashing patterns and a scroll pattern. When an LED indicates a continuous single-flash
pattern, network management has disabled the port. A continuous double-flash pattern indicates the
wrong speed. In a scroll pattern, the LEDs turn on and off in a set order.
10 DECmau 900TL