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2-WIRE IDSL LINE DRIVER RACK CARDS
D.3 DIP-Switch Configuration
The module features an eight-position DIP switch mounted on the rear of the
printed circuit board. Use these switches to configure G.703 operational and
timing modes. Figure D-2 shows the position of the DIP switches on the board.
Figure D-2. DIP switches on the rear card.
Switch S1: Reserved for future use
Switch S1 is reserved for future use and should remain in the Off position.
Switch S2: Operation Mode
Use switch S2 to set the rear card module for either clear channel or octet timing
mode. Most installations use clear channel (64-kbps) mode operation, though
some installations may use octet timing mode.
When operating in octet timing mode, the G.703 Rear Card facilitates a sense of
frame synchronization by inserting bipolar violations in the AMI coding structure.
When the Card is set to octet timing mode (On position), all communications
equipment in the channel must be configured to communicate at 128 kbps
(64 kbps data plus 64 kbps octet framing pattern). Additionally, all terminal
equipment must support octet timing. When set to clear channel mode, the system
operates at 64 kbps.
DIP switches
