MC33591MOD434 Freescale Semiconductor, MC33591MOD434 Datasheet - Page 5

• Manufacturer Part Number: MC33591MOD434
• Description: BOARD EVALUATION FOR MC33591 RX
• Manufacturer: Freescale Semiconductor
• Type: Receiverr

Specifications of MC33591MOD434

• Contents: Module and Misc Hardware
• For Use With/related Products: MC33591 434 MHz RF Module
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

COMMUNICATION PROTOCOL
MANCHESTER CODING DESCRIPTION
during the second half-bit.
achieve a correct clock recovery, Manchester coded data must have a duty cycle between:
PREAMBLE, ID, HEADER WORDS AND MESSAGE DESCRIPTION
Register 2. The complement of the ID word is recognized as an ID word. ID word is sent at the same data rate as
data.
It enables:
Figure 4 defines the Preamble word in OOK and FSK modulation. Preamble content must be carefully defined in
order not to be decoded as an ID or Header word.
Manchester coding is defined as follows: data is sent during the first half-bit, complementary data is sent
The signal average value is constant. This allows clock recovery from the data stream itself. In order to
The following description applies if the Data Manager is enabled (DME=1).
The ID word is a Manchester coded byte whose content has been previously loaded in the Configuration
A preamble is required:
MOTOROLA
- 48% and 52% in OOK,
- 45% and 55% in FSK.
- before ID,
- before Header if HE=1,
- before data if HE=0.
- in case of OOK modulation, AGC to settle,
- in case of FSK modulation, data slicer reference voltage to settle,
- in any case, clock recovery.
OOK Modulation:
FSK Modulation:
Data slicer reference settling time
2 ‘1’ NRZ at 9.6kBd,
1 ‘1’ NRZ at 4.8kBd
AGC settling time
‘1’ NRZ > 200µs
3 ‘1’ or ‘0’ Manchester
0
at data rate
i.e.:
1
Freescale Semiconductor, Inc.
Figure 3: Manchester coding example
For More Information On This Product,
0
Figure 4: Preamble definition
Clock recovery
‘0’ Manchester
0
MC33591 Technical Data
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at data rate
‘1’ or ‘0’ Manchester
1
Clock recovery
at data rate
1
0
ID
Manchester coded
Original data
ID
COMMUNICATION PROTOCOL
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