mpc823rg Freescale Semiconductor, Inc, mpc823rg Datasheet - Page 645

• Manufacturer Part Number: mpc823rg
• Description: Mpc823 Powerquicc Integrated Communications Processor For Portable Systems
• Manufacturer: Freescale Semiconductor, Inc

16.9.11.1 ENCODING AND DECODING DATA WITH A DPLL. Each serial
communication controller contains a digital phase-locked loop unit that can be programmed
to encode and decode SCCx data as NRZ, NRZI Mark, NRZI Space, FM0, FM1,
Manchester, and Differential Manchester. Examples of the different encoding methods are
illustrated in Figure 16-70.
If you do not want to use the DPLL, you can choose NRZ coding in the RENC and TENC
bits of the GSMR_L. The coding is defined as follows:
DIFFERENTIAL
MANCHESTER
MANCHESTER
• NRZ—A one is represented by a high level for the duration of the bit and a zero is
• NRZI Mark—A one is represented by no transition at all. A zero is represented by a
• NRZI Space—A one is represented by a transition at the beginning of the bit (the level
• FM0—A one is represented by a transition only at the beginning of the bit. A zero is
• FM1—A one is represented by a transition at the beginning of the bit and another
NRZI SPACE
NRZI MARK
represented by a low level.
transition at the beginning of the bit (the level present in the preceding bit is reversed).
present in the preceding bit is reversed). A zero is represented by no transition at all.
represented by a transition at the beginning of the bit and another transition at the
center of the bit.
transition at the center of the bit. A zero is represented by a transition only at the
beginning of the bit.
DATA
NRZ
FM0
FM1
Freescale Semiconductor, Inc.
Figure 16-70. DPLL Encoding Examples
For More Information On This Product,
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MPC823 REFERENCE MANUAL
Go to: www.freescale.com
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Communication Processor Module
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