Knowledge Base

sync word doesnt make any difference

I've been using the SX1272 in LoRa mode for some time, but I have found something weird!
If my transmitter and receiver have different RegSyncWord (0x39) values, they still communicate fine.
I have read the values back from the chips and confirmed they are different and NOT the default 0x12, but it still receives the transmitter.
Any ideas what I'm missing?

The LoRa "syncword" should be considered (along with the preamble symbols) as a Start of Frame Delimiter (SFD) to provide a measure of the correlation between the transmitted packet and that received.

Every LoRa "syncword" symbol combination has a different resultant cross-correlation coefficient which can be considered as probability error functions for false-detection and false-rejection.

Semtech Support
Yes, I know what a sync word does.. but if I change the sync word, I shouldn't receive it right?
That's why 12 private or 34 lorawan is used.
But whatever value I program, it always received.. why is that?
I have the same odd behaivour.
I'm able to communicate two nodes between them with diferent sync word. why??

I too am finding the same issue.

I am also using Implicit Header Mode. Is that making a difference?