Siemens INSYS Pocket ISDN-TA Operating Manual page 13

Installation
The 4 LEDs at the right show the status of the serial interface to the PC:
R : shows activity of receiving data from the POCKET ISDN-TA and ISDN
line
T : shows activity of transmitted data from the terminal
DTR : shows the status of DTR line, i.e. the terminal is trying to connect via
the POCKET ISDN-TA
DCD : represents the status of the DCD line (V.24); shows normally the
connection to an access server.
Both LEDs, B1 and B2, show the connection state of the ISDN B channels:
If ON this B channel is occupied due to an incoming or outgoing connection (data
or voice).
Both of the LEDs, L1 and L2, show the overall status of the POCKET ISDN-TA in coded
form. The following list describes the view for an error free power on sequence of
the POCKET ISDN-TA.
Status
1. Power-On-Phase, wait
2. Active phase, ISDN ok
3. Connected, ISDN data
connection established
LED Legend:
A complete list you can find in the appendix "LED displays"
⊗
On
Θ
Continuously blinking
O
Off
L1 L2
⊗ Θ
(about 2 sec)
⊗ O
⊗ ⊗
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