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Sync Word for Modem Lora

Associate II


Hello ST Community,

I am currently working with a STM32WL 55JC  and I need assistance with setting the sync word for both the transmitter and receiver. Here are the details of my setup.


Here I have configured my module to USE_MODEM_LORA and these are the packet params of the USE_MODEM_LORA


This below is the set sync word function whish is present in the radiodriver.c file



here is the another function which is 



I want to use the private syncword how do i do that when i use  USE_MODEM_LORA.

ST Employee

Hello @Shivaprasad 

To configure a private syncword in a STM32WL LoRa project when using USE_MODEM_LORA, you would typically follow these steps:

  1. Set the Packet Type to LoRa: Use the Set_PacketType() function to set the packet type to LoRa.

  2. Define the Frame Format: Use the Set_PacketParams() function to define the frame format according to your requirements.

  3. Set the Sync Word: Use the Write_Register() function to define the synchronization word in the associated packet type SUBGHZ_xSYNCR(n) registers. The synchronization word for private networks is different from the public LoRa network sync word.

  4. Set the Network to Private: Use the RadioSetPublicNetwork() function to set the network to private by passing false as an argument.

Best Regards.


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