cx29600 Mindspeed Technologies, cx29600 Datasheet - Page 95

• Manufacturer Part Number: cx29600
• Description: Optiphytm - M155 Sts-3 Sonet/sdh Multiplexer
• Manufacturer: Mindspeed Technologies

CX29600
CX29600 Data Sheet
2.8.1 Line Loopback
Figure 2-25. Line Loopback Diagram
2.8.2 Source Loopback
Figure 2-26. Source Loopback Diagram
29600-DSH-001-B
STS-3c/STM
STS-3c/STM
2.8 Loopback Modes
Loopbacks are diagnostic tools used to verify the data path. The CX29600 has
two loopback modes: Line Loopback (which checks the line between a remote
device and the PHY) and Source Loopback (which checks that the host (the
SI-Bus) is communicating with the PHY).
Line loopback is enabled or disabled in bit 0 of the CLKREC register. When Line
loopback is enabled, all incoming data on the Receive Line Interface is
retransmitted out the Transmit Line Interface. The received data is also passed
through the PHY’s normal path to be output on the SI-Bus interface.
Source loopback is enabled and disabled in bit 1 the CLKREC register. When
source loopback is enabled, all data transmitted by the CX29600 is also looped
back through the Receive Line Interface. Data from the LIU is ignored.
CDR
CDR
Mindspeed Technologies
Framer
STS-3
Framer
STS-3
Interface
SI-Bus
Interface
™
SI-Bus
2.0 Functional Description
2.8 Loopback Modes
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