Data Sheet
Page 38
RFM69HCW
Tel: + 86-755-82973805 Fax: +86- 755-82973550 E-mail: sales@hoperf.com http:// www.hoperf.com
4.2.4. Rx Start Procedure
As described in the former sections, the RxReady interrupt warns the uC that the receiver is ready.
In Continuous mode with Bit Synchronizer
, the receiver will start locking its Bit Synchronizer on a minimum or 12 bits of
received preamble (see section 3.4.13 for details), before the reception of correct Data, or Sync Word (if enabled) can
occur.
In Continuous mode without Bit Synchronizer
, valid data will be available on DIO2/DATA right after the RxReady
interrupt.
In Packet mode
, the receiver will start locking its Bit Synchronizer on a minimum or 12 bits of received preamble (see
section 3.4.13 for details), before the reception of correct Data, or Sync Word (if enabled) can occur.
4.2.5. Optimized Frequency Hopping Sequences
In a frequency hopping-like application, it is required to turn off the transmitter when hopping from one channel to another,
to avoid spectral splatter and obtain the best spectral purity.
Transmitter hop from Ch A to Ch B: it is advised to step through the Rx mode:
(0) RFM69HCW is in Tx mode in Ch A
(1) Program the RFM69HCW in Rx mode
(2) Change the carrier frequency in the RegFrf registers
(3) Turn the transceiver back to Tx mode
(4) Respect the Tx start procedure, described in section 4.2.2
Receiver hop from Ch A to Ch B:
(0) RFM69HCW is in Rx mode in
Ch A
(1) Change the carrier frequency in the RegFrf registers
(2) Program the RFM69HCW in FS mode
(3) Turn the transceiver back to Rx mode
(4) Respect the Rx start procedure, described in section 4.2.4
Note all sequences described above are assuming that the sequencer is turned on (SequencerOff=0 in RegOpMode).