Overview DXLink Fiber
13
Instruction Manual – DXLink Fiber Transmitters and Receivers
DXLink Fiber Hardware Compatibility
This section applies to TX-to-RX standalone pairs and to DXLink Fiber Input or Output Boards and their corresponding
TX or RX units. (Duplex and Simplex boards can be used in the same enclosure.)
Connections are allowed between matching hardware (Duplex to Duplex or Simplex to Simplex) as well as between
mixed hardware (Simplex to Duplex or Duplex to Simplex) as long as the constraints of multimode to multimode and
single mode to single mode are maintained.
Important:
Compatibility between hardware requires matching model types: multimode to multimode and
single mode to single mode.
The next section explains the functionality and limitations inherent in the three Directional Modes used for
communication control. An understanding of these modes is necessary, especially if you are not using the default for the
specific hardware type (Duplex or Simplex).
DXLink Fiber Directional Modes
DXLink Fiber Directional Modes include Bidirectional Mode, Unidirectional Mode, and Data Link-lost Mode. DXLink
Fiber, Duplex hardware has a default setting of Bidirectional Mode, but can be configured for Unidirectional Mode or
drop into Data Link-lost Mode (when the return path is removed or not connected). DXLink Fiber, Simplex hardware
only uses Unidirectional Mode.
Note:
For instructions on setting Duplex TXs and RXs to a particular Directional Mode, see “Duplex Hardware
Directional Mode Configuration” on page 56. For instructions on configuring DXLink Fiber, Duplex Input and
Output Boards, see the “Instruction Manual – Enova DGX 8/16/32/64 Digital Media Switchers.”
Bidirectional Mode
When data flows in two directions, the flow is bidirectional. For example, a source device sends audio, video, and
communication data to a TX. From the TX, all three signals are sent via fiber to an input board on the switcher. The input
board routes the audio and video to an output board, while the integrated Master processes the communication data. The
output board sends audio and video (along with any necessary communication data) via its RX to the destination device.
If needed, communication data from the destination device can return to the Master for processing via the same path.
Bidirectional is the default Directional Mode for DXLink Fiber, Duplex units if both fiber strands are connected. Setting
DIP switch #4 to ON enables Unidirectional Mode (see below) and the lack of a return fiber path results in the unit
dropping into Data Link-lost Mode (see below also).
Unidirectional Mode
When data flows in only one direction, the flow is unidirectional. For example, an audio/video signal travels from a
Transmitter to a Receiver and no signals are passed back to the Transmitter. In Unidirectional Mode, the Receiver does
not send an optical signal trying to establish a return data path connection. Simplex hardware always operates in this
mode and does not require additional setup. Unidirectional Mode is a configurable setting for Duplex hardware which
requires setting the DIP switch’s #4 Toggle on the bottom of the Transmitter or Receiver.
Data Link-lost Mode
When a system is configured for Bidirectional Mode, but the data return path has been removed or is not connected, the
system drops into Data Link-lost Mode. In Data Link-lost Mode, the Transmitter only sends audio and video to the
Receiver over a single fiber path, but both units are actively ready for the addition of the return path which will enable
Bidirectional Mode. For example, an audio/video signal travels from a Transmitter to a Receiver and no signals are
passed back to the Transmitter, but the Receiver’s return laser still transmits light and attempts to establish a connection.
Important:
When using Duplex hardware in mixed modes (where boards and their units are configured for
different Directional Modes) or using both Duplex and Simplex hardware (where the Duplex hardware is in
Bidirectional Mode), the hardware must be configured to avoid Data Link-lost Mode (see Caution above).
Caution:
In Data Link-lost Mode, the data return path is disconnected but both of the transceiver lasers are
still active. If left uncovered, transceiver lasers may constitute a health hazard. This hazard should be
avoided by restoring Bidirectional Mode (see page 56), configuring DXLink Fiber units for Unidirectional
Mode (see page 56), or covering exposed lasers.
