MRF24XA_15 Datasheet, PDF (102/258 Pages) Microchip Technology – Low-Power, 2.4 GHz ISM-Band IEEE 802.15.4™ RF

MRF24XA
4.6 Frame-On-Air/Air-Data-Rate
In the Originator of the frame, FRMFMT and DR<2:0>
select the air-data-rate and the frame format. The
PRMBHLD bit indefinitely holds out the preamble. For
more information on register definitions, refer to
Register 4-2.
The recipient of the frame can receive the frame
formats that FRMFMT and RATECON<7:2> selects.
The Recipient sends the Acknowledge using the same
frame format as the acknowledged frame, except for
the agility, see Section 7.1 “Channel Agility”. The
Originator must set RATECON<7:2> adequately to
receive the ACK frame.
RATECON<1> selects between Legacy and Optimal
PHY frame format. This is set independently from the
rate or the MAC protocol using the MAC operation.
FIGURE 4-7:
FRAME-ON-AIR/AIR-DATA-RATE
PRMBHLD
Preambulum
SFD Length
MAC Frame
Preamble type:
Legacy: 192 µs fix
Optimal: Duration scales reciprocally
with DR
FRMFMT:
0 IEEE 802.15.4™ standard compliant
1 Proprietary
DS70005023C-page 102
Preliminary
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