AL211 Allayer Communications, AL211 Datasheet - Page 11

• Manufacturer Part Number: AL211
• Description: Fast Ethernet Fiber to TP Media Converter
• Manufacturer: Allayer Communications

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The AL211 can also be used as a full duplex media extender or 850nm to 1300nm media converter
by turning the scrambler off. To turn the scrambler off, the pin SCRen should be connected to
ground.
The AL211 will propagate the idle signals from media to media. After reception of the idle signal
(all “1s”), the device will then transmit an idle signal to the opposite ports, i.e. TP to fiber or fiber to
TP. There are two types of link-failure; receive or remote fault (also known as far-end fault).
The AL211 supports redundant link through the use of DATAoff and Redun# signals. The
redundant link function is only available for the FO port. An implementation of a redundant link is
shown in
fault signaling support required) and two AL211’s.
There are two likely scenarios; either the transmit link fault or the receive link fault could trigger
the redundant link.
2.7 Scrambler
2.8 Fault Propagation
2.9 Redundant Link
Figure
1. TP receive link-failure. In the event of a TP receive link-failure, the AL211 will
2. Fiber receive link-failure. In the event of a fiber receive link-failure, the AL211
3. TP transmit link-failure. In the event of a TP transmit link-failure, the TP far-end
4. Fiber transmit link-failure. In the event of a fiber transmit link-failure, the far-end
1-6. A redundant link can also be configured with two fiber switch ports (far-end
cease to transmit an idle signal to the fiber optic driver. A valid TP link signal can
be either a 10Base-T link pulse or a 100Base-TX idle signal.
will cease to transmit an idle signal to the TP driver and put the driver into high
impedance. The device will also send a remote fault signal to the fiber optic driver
in addition to asserting the Redun# signal.
transceiver will cease to transmit an idle signal and start transmitting FLP to the
AL211. Since the AL211 does not understand FLP, it will continue to transmit an
idle signal to the fiber optic driver.
transceiver (with remote fault signaling capability) will transmit an RF signal to
the AL211. As a result, the AL211 will perform two tasks: cease to transmit an
idle signal to the TP driver and put the driver into high impedance asserting the
Redun# signal.
Reference Only / Allayer Confidential
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