Datasheet

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SX1272/73
WIRELESS, SENSING & TIMING DATASHEET
Rev. 2 - July 2014
©2014 Semtech Corporation
Figure 38. Data Whitening Polynomial
4.2.14.8. Beacon Tx Mode
In some short range wireless network topologies a repetitive message, also known as beacon, is transmitted periodically
by a transmitter. The Beacon Tx mode allows for the re-transmission of the same packet without having to fill the FIFO
multiple times with the same data.
When BeaconOn in RegPacketConfig2 is set to 1 the FIFO can be filled only once in Sleep or Stdby mode with the required
payload. After a first transmission, FifoEmpty will go high as usual, but the FIFO content will be restored when the chip
exits Transmit mode. FifoEmpty, FifoFull and FifoLevel flags are also restored.
This feature is only available in Fixed packet format with the Payload Length smaller than the FIFO size. The control of the
chip modes (Tx-Sleep-Tx....) can either be undertaken by the microcontroller, or be automated in the Top Sequencer. See
example in section
4.2.14.8.
The Beacon Tx mode is exited by setting BeaconOn to 0 and clearing the FIFO by setting FifoOverrun to 1.
4.2.15. io-homecontrol
®
Compatibility Mode
The SX1272/73 features a io-homecontrol
®
compatibility mode. Please contact your local Semtech representative for
details on its implementation.
X
7
X
6
X
5
X
4
X
3
X
2
X
1
X
0
X
8
LFSR Polynomial =X
9
+ X
5
+ 1
Transmit data
Whitened data