Datasheet

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SX1272/73
WIRELESS, SENSING & TIMING DATASHEET
Rev. 2 - July 2014
©2014 Semtech Corporation
4.2.6.6. Receiver Hopping, Rx to Rx
Two methods are possible:
Figure 22. Receiver Hopping
The second method is quicker and should be used if a very quick RF sniffing mechanism is to be implemented.
4.2.6.7. Tx to Tx
Figure 23. Transmitter Hopping
4.2.7. Receiver Startup Options
The SX1272/73 receiver can automatically control the gain of the receive chain (AGC) and adjust the receiver LO
frequency (AFC). Those processes are carried out on a packet-by-packet basis. They occur:
 When the receiver is turned On.
 When the Receiver is restarted upon user request, through the use of trigger bits RestartRxWithoutPllLock or
RestartRxWithPllLock in RegRxConfig.
 When the receiver is automatically restarted after the reception of a valid packet or after a packet collision.
Rx Mode,
Channel A
1. set new Frf
2. set RestartRxWithPllLock
Timeline
0TS_HOP
+TS_RE
Rx Mode,
Channel B
First method
Rx Mode,
Channel A
1. set FastHopOn=1
2. set new Frf (*)
3. wait for TS_HOP
Timeline
0
~TS_HOP
Rx Mode,
Channel B
Second method
(*) RegFrfLsb must be written to
trigger a frequency change
1. set new Frf (*)
2. set FSTx mode
FSTx
Timeline
~PaRamp
+TS_HOP
~PaRamp
+TS_HOP
+TS_TR
0
Tx Mode,
Channel A
Tx Mode,
Channel B
Set Tx mode