SX1232
WIRELESS & SENSING
DATASHEET
4.4.2. Automatic Restart after valid Packet Reception
The bits AutoRestartRxMode in RegSyncConfig control the automatic restart feature of the SX1232 receiver, when a valid
packet has been received:
If AutoRestartRxMode = 00, the function is off, and the user should manually restart the receiver upon valid packet
reception (see section 4.4.1).
If AutoRestartRxMode = 01, after the user has emptied the FIFO following a PayloadReady interrupt, the receiver will
automatically restart itself after a delay of InterPacketRxDelay, allowing for the distant transmitter to ramp down, hence
avoiding a false RSSI detection on the “tail” of the previous packet.
If AutoRestartRxMode = 10 should be used if the next reception is expected on a new frequency, i.e. Frf is changed
after the reception of the previous packet. An additional delay is systematically added, in order for the PLL to lock at a
new frequency.
4.4.3. Automatic Restart when Packet Collision is Detected
At any stage during reception, the receiver is able to spontaneously detect a packet collision, and restart itself. Collisions
are detected by a sudden rise in received signal strength, detected by the RSSI blocks. This function can be useful in star
network configurations, where a master node may be transmitted packet at random times, from different end-points located
at various distances.
The collision detector is enabled by setting bit RestartRxOnCollision to 1.
The decision to restart the receiver is based on the detection of RSSI change. The sensitivity of the system can be adjusted
in 1dB steps, with RssiCollisionThreshold in RegRxConfig.
Rev 3 - August 2012
Page 43
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