Data Sheet

LJ1269HC
Rev1.0 Page 45 Web: www.ljelect.com
Table 20 Status of FIFO when Switching Between Different Modes of the Module
From
To
FIFO status
Comments
Stdby
Sleep
Not cleared
Sleep
Stdby
Not cleared
Stdby/Sleep
Tx
Not cleared
To allow the user to write the FIFO in Stdby/Sleep
before Tx
Stdby/Sleep
Rx
Cleared
Rx
Tx
Cleared
Rx
Stdby/Sleep
Not cleared
To allow the user to read FIFO in Stdby/Sleep mode
after Rx
Tx
Any
Cleared
5.2.3. Sync Word Recognition
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 28 below.
Figure 27. Sync Word Recognition
During the comparison of the demodulated data, the first bit received is compared with bit 7 (MSB) of RegSyncValue1 and the
last bit received is compared with bit 0 (LSB) of the last byte whose address is determined by the length of the Sync word.
W hen the programmed Sync word is detected the user can assume that this incoming packet is for the node and can be
processed accordingly.
SyncAddressMatch is cleared when leaving Rx or FIFO is emptied.
Sub GHz FSK/OOK Transceiver Module DATASHEET