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ASYNC MP LINE DRIVER CARD
5. Operation
Once you have configured each Async MP Line Driver Card and connected the
cables, you are ready to operate the units. This Chapter describes the LED status
monitors, the power-up procedure and the built-in loopback test modes.
5.1 LED Status Monitors
The Async MP Line Driver Card features ten front-panel status LEDs that indicate
the condition of the modem and communication link.
Figure 5-1
shows the
relative front-panel positions of the LEDs. A description of each LED’s function
follows.
Figure 5-1. Front Panel, Showing LED Positions.
• The green PWR LED glows when power is applied to the Card through its mid-
plane chassis connection.
• The green TD and RD indicators blink to show positive-state data activity. The
red TD and RD indicators blink to show negative-state data activity. Solid red
indicates a connection in an idle state.
• The green “Control In” and “Control Out” indicators glow solid to show the
control signal is on. The red “Control In” and “Control Out” indicators glow
solid to show the control signal is off. When the Card is connected to a DTE,
