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Introduction and Description
LED Indicators
The ten LED indicators on the front panel (see figure below) of the MTA1 28ST/NT report status and line activity.
Transmit Data
Flashes when data is being transmitted (on for a space, off for a mark).
Receive Data
Flashes when data is being received (on for a space, off for a mark). Link
Status
For EuroISDN NET3, INS64, and VN4 switch protocols, lights when the TA is turned on. For US
Bearer Channel 1
When lit, indicates active data or voice connection on bearer channel 1.
Bearer Channel 2
When lit, indicates active data or voice connection on bearer channel 2.
Terminal Ready
Lights to indicate that the computer is communicating with the MTA1 28ST/NT, so the MTA1 28ST/NT can answer an incoming call.
Off Hook
Lights when analog equipment on AUX port is active or
128 Kbps
Lights to indicate that the B channels have been multiplexed into a single 128 Kbps communications link.
Data Protocol
Lights in combination with P2 and 128 LEDs to indicate which data protocol (V.110, V. 120, X.75, PPP, MLPPP) is in use as shown in the table below.
Data Protocol
Lights in combination with P1 and 128 LEDs to indicate which data protocol (V.110, V. 120, X.75, PPP, MLPPP) is in use as shown in the table below.
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