5
X
RS-232,485 + 2
X
E
THERNET
/2 M
BIT
/
S
G.703 (G.704) M
ULTIPLEXER
O
PERATING
M
ANUAL
IOA81-1E
15
August 2004
3.7 Operating modes of tributary channels
Transmission between line ports A and B and tributary channels C1
÷
C7 can be effected
in one of two ways:
•
With interrupted transmission path - DROP mode,
•
Without interrupting the transmission path - DROP & CONTINUE mode.
Selection of operating mode is made for each of seven tributary channels individually by
using „MODE OF OPERATION” switches.
Operating mode with interrupted transmission path -Drop mode
If the tributary channel equivalent to the nth time slot is selected and the „MODE OF
OPERATION” switch is set to the DROP position, then the transmission path between A and
B ports for this slot is interrupted in both directions. Connection between selected tributary
channel and A or B port through this slot is closed, and the “0” signal is sent in outgoing di-
rection of the opposite port.
In the example shown on Fig. 18 the C1 tributary channel is selected. This channel is as-
sociated with time slot number 2. Transmission path between ports A and B for the slot 2 is
interrupted in both directions. Connection between selected C1 channel and the port A through
this slot is closed. In the interrupted slot the “0” signal is sent in outgoing direction of the port
B.
DMUX
MUX
Output of line
port A
Input of line
port B
Input of line
port A
Output of line
port B
Initial slot selected by using
CONFIGURATION switches
CHANNEL DIRECTION
TRIBUTARY CHANNEL
CONFIGURATION
A
B
C1
MODE OF OPERATION
Drop
Drop&c
Fig. 18.
Dropping of time slots with interrupted transmission path
