SX1232
WIRELESS & SENSING
DATASHEET
State Machine
Sequencer Off
&
Initial mode = Sleep or Standby
IdleMode = 1 : Sleep
Start bit set
LowPowerSelection = 1
LowPower
Selection
Start
Idle
FromStart = 00
On T1
FromIdle = 1
FromRxTimeout = 10
On SyncAdress
FromReceive = 101
On T2
Sequencer Off
RxTimeout
Receive
On RxTimeout
Figure 50. Wake On SyncAddress State Machine
This example configuration is achieved as follows:
Table 35 Listen Mode with SyncAddress Condition Settings
Variable
Effect
IdleMode
1 : Sleep mode
FromStart
LowPowerSelection
00 : To LowPowerSelection
1 : To Idle state
FromIdle
FromReceive
FromRxTimeout
1 : To Receive state on T1 interrupt
101 : To Sequencer off on SyncAddress interrupt
10 : To LowPowerSelection
T
T
T
should be set to just long enough to catch a preamble (depends on PreambleDetectSize and BitRate).
TimeoutRxPreamble
should be set to 64 µs (shortest possible duration).
Timer1
Timer2
is set so that T
T
defines the time between two start of reception.
Timer1 + Timer2
In order to insure packet detection and optimize the receiver power consumption, the received packet Preamble should be
defined so that T - T , with T = (SyncSize + 1)*8/BitRate.
T
Preamble = Timer2
SyncAddress
SyncAddress
An example of DIO configuration for this mode is described in the following table:
Table 36 Listen Mode with PreambleDetect Condition Recommended DIO Mapping
DIO
0
1
2
3
Value
01
00
11
00
Description
CrcOk
FifoLevel
SyncAddress
FifoEmpty
4
11
PreambleDetect – Note: MapPreambleDetect bit should be set.
Rev 3 - August 2012
Page 89
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