MRF24XA_15 Datasheet, PDF (218/258 Pages) Microchip Technology – Low-Power, 2.4 GHz ISM-Band IEEE 802.15.4™ RF

MRF24XA
9.7 Physical Framing
Physical frame durations for the different data rates are
shown in Table 9-6. Duration is expressed in payload
byte time.
TABLE 9-6: FRAME DURATION
Frame Formats
T [µs/byte]
Duration expressed in payload byte time (T)
Preamble
SFD
Length
PHY payload
Proprietary 125 kbps
64
4
1
1
N
Standard 250 kbps
32
4
1
1
N
Proprietary 500 kbps
16
4
1
1
N
Proprietary 1 Mbps
8
4
1
1
N
Proprietary 2 Mbps
4
8
2
1
N
Different frame data rates are recognized and pro-
cessed based on the recognized SFD field of the PHY
frame. Figure 4-7 describes the basic PHY frame struc-
ture. RATECON<7:2> bits can disable the reception of
the unwanted data rate frames.
TABLE 9-7: USED SFD FIELDS FOR VARIOUS DATA RATES
Preamble Type
Data Rate Pattern
Used SFD Field
Optimal
Pattern_2000
Pattern_1000
<SFD1, SFD6>
<SFD2, SFD7>
Pattern_500
Pattern_250 proprietary
Pattern_250 standard
Pattern_125
SFD3
SFD4
0xA7
<SFD5, SFD6>
Legacy
Pattern_2000
Pattern_1000
Pattern_500
Pattern_250 proprietary
Pattern_250 standard
Pattern_125
SFD1
SFD2
SFD3
SFD4
0xA7
<SFD5, SFD6>
Fault Tolerance
Exact match required
Maximally two non-contiguous
two-element burst error
Exact match required
Exact match required
Exact match required
Maximally two faulty nibbles
from four
Exact match required
Exact match required
Exact match required
Exact match required
Exact match required
—
DS70005023C-page 218
Preliminary
 2015 Microchip Technology Inc.