SX1231
ADVANCED COMMUNICATIONS & SENSING
DATASHEET
FifoLevel
1
0
B
B+1
# of bytes in FIFO
Figure 24. FifoLevel IRQ Source Behavior
Note - FifoLevel interrupt is updated only after a read or write operation on the FIFO. Thus the interrupt cannot be
dynamically updated by only changing the FifoThreshold parameter
- FifoLevel interrupt is valid as long as FifoFull does not occur. An empty FIFO will restore its normal operation
5.2.2.4. FIFO Clearing
Table below summarizes the status of the FIFO when switching between different modes
Table 18 Status of FIFO when Switching Between Different Modes of the Chip
From
Stdby
To
Sleep
Stdby
Tx
FIFO status
Not cleared
Not cleared
Not cleared
Cleared
Comments
Sleep
Stdby/Sleep
Stdby/Sleep
Rx
To allow the user to write the FIFO in Stdby/Sleep before Tx
To allow the user to read FIFO in Stdby/Sleep mode after Rx
Rx
Tx
Cleared
Rx
Stdby/Sleep
Any
Not cleared
Cleared
Tx
5.2.3. Sync Word Recognition
5.2.3.1. Overview
Sync word recognition (also called Pattern recognition) is activated by setting SyncOn in RegSyncConfig. The bit
synchronizer must also be activated in continuous mode (automatically done in Packet mode) .
The block behaves like a shift register; it continuously compares the incoming data with its internally programmed Sync
word and sets SyncAddressMatch when a match is detected. This is illustrated in Figure 25 below.
Rev 2 - Nov 2009
Page 44
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