RFM69W Datasheet, PDF (32/78 Pages) List of Unclassifed Manufacturers – ISM TRANSCEIVER MODULE

To ensure a proper behavior of the FEI:
‹ _{The operation must be done during the reception of preamble}
The frequency error, in Hz, can be calculated with the following formula:
RFM69W
RFSMX16293W9 in Rx mode
Preamble-modulated input signal
Signal level > Sensitivity
Set FeiStart
=1
FeiDone
No
=1
Yes
Read
FeiValue
Figure 14. FEI Process
3.4.15. Automatic Frequency Correction
The AFC is based on the FEI block, and therefore the same input signal and receiver setting conditions apply. When the
AFC procedure is done, AfcValue is directly subtracted to the register that defines the frequency of operation of the
module, F_RF. The AFC can be launched:
‹ Each time the receiver is enabled, if AfcAutoOn = 1
‹ Upon user request, by setting bit AfcStart in RegAfcFei, if AfcAutoOn = 0
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