cx28365 Mindspeed Technologies, cx28365 Datasheet - Page 67

• Manufacturer Part Number: cx28365
• Description: X12, X6, X4 T3/e3 Framer And Atm Cell Transmission Convergence Sublayer Processor
• Manufacturer: Mindspeed Technologies

CX28365/6/4 Data Sheet
2.1.2
2.1.2.1
Figure 2-12. Receiver Line Input Timing
2.1.2.2
500028C
RxPOSI
RxNEGI
RxCKI
Receiver Operation
Line Signals
The line receive interface consists of three input signals:
The line interface can be placed in Bipolar or Unipolar mode and the RxAMI field of
the Feature1 line code can be selected as AMI or B3ZS/HDB3. See register CR04.
The data stream is sampled from the data (RxPOSI and RxNEGI, or RxNRZ and
LCVI) pins on either the rising or the falling edge of RxCKI (CR08 register).
Figure 2-12
is sampled on the rising edge of the clock.
The CX2836x decoder converts the bipolar signal to a unipolar stream based on AMI/
B3ZS/HDB3 line code and detects LCV, if any. The decoder is bypassed in NRZ
(unipolar) mode.
System Signals
The system-side receive interface consists of four output signals:
RxCKI clocks the internal circuits and drives both output clocks (RxGCKO and
REXTCKO). Output signals (RxDATO and RxSync) change on either the rising or
falling edge of the output clocks (as defined in the CR08 register).
RxGCKO functionality is software-selectable to one of five modes:
1.
2.
3.
Preliminary Information/Mindspeed Proprietary and Confidential
RxGCKO—Data clock, gapped during Opportunity bits (programmable)
RxDATO—Data (all payload and overhead)
REXTCKO—Receive supplementary clock, (programmable)
RxSync—Frame synchronization output signal
RxCKI—Receive clock derived from incoming data (44.736MHz or
34.368 MHz).
RxPOSI/RxNRZ—In Bipolar mode, is positive polarity data. In Unipolar mode,
is NRZ data.
RxNEGI/LCVI—In Bipolar mode, is negative polarity data. In Unipolar mode,
reports an LCV (or tied to ground).
illustrates the relation between data (100100110) and clock assuming data
Mindspeed Technologies™
Functional Description
500028_025
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