Implicit Header Valid IRQ (SX127x -> SX126x migration issue)

On SX127x LoRa mode, documented functionality is that Header Valid IRQ will trigger on start of packet (i.e. sync detect) for implicit mode packets.

On SX126x LoRa mode, it is not clear how to get an IRQ to occur at the beginning of packet detection. Header Valid IRQ does not seem to work for implicit frames. Preamble Detect IRQ is not as reliable, and I don’t know if it accounts for sync word.

I am hoping there is some configuration or workaround to have an IRQ triggered on sync word detect, for SX126x. This is critical for my application, which does link monitoring during packet reception.


Preamble Detect IRQ is triggered during the reception of the preamble - it means that enough LoRa symbols are received to be synced. Did you experience any issue with this IRQ source?

Concerning the sync word detection, it is only available for GFSK modulation.