cx29503 Mindspeed Technologies, cx29503 Datasheet - Page 89

• Manufacturer Part Number: cx29503
• Description: Cx29503 Broadband Access Multiplexer Data Sheet
• Manufacturer: Mindspeed Technologies

CX29503 Data Sheet
2.10.5
2.10.5.1
2.10.5.2
29503-DSH-002-B
Details of Overhead TSB
Overhead Data Path
The overhead TSB frame transports PDH, SONET, or SDH overhead communication
channels and data for monitoring and configuring the CX29503 registers.
Overhead TSB Frame Stuff Byte Compensation
Stuff bytes are inserted into the overhead TSB to compensate for differences in the
data rate of the TSB and the data rate of the data carried on the bus in both the
transmit and receive directions.
In general, the CX29503 asserts the transmit and the receive stuff signals to initiate or
mark the insertion of stuff bytes into overhead TSB frames to compensate for data rate
offsets that exist between the TSB bandwidth and the bandwidth of the data carried on
the bus. For example, when the overhead TSB operates at a data rate of 12.96 Mbps,
the bandwidth allocated to each of the 84 time slots is approximately 154.29 kbps.
Time slots are assigned to each overhead data path to ensure that the TSB bandwidth
exceeds the bandwidth of the data path.
To compensate for this bandwidth difference, the CX29503 asserts stuff signals to
mark the insertion of stuff bytes into overhead TSB frames. The overhead TSB
bandwidth is also configured to exceed the required bandwidth for the other overhead
TSB data rates of 11.184 Mbps and 8.592 Mbps.
Mindspeed Technologies™
Preliminary Information
Functional Description
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