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sandeepmistry / arduino-LoRa

An Arduino library for sending and receiving data using LoRa radios.
MIT License
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Corrupted header may let corrupted packets to go through even CRC is enable? #443

Open IoTThinks opened 3 years ago

IoTThinks commented 3 years ago

I realized even I enableCrc(), visibble corrupted packets are still received. Possible reason is due to corrupted header.

    // check packet header integrity
    if(_crcEnabled && (_mod->SPIgetRegValue(SX127X_REG_HOP_CHANNEL, 6, 6)) == 0) {
      // CRC is disabled according to packet header and enabled according to user
      // most likely damaged packet header
      clearIRQFlags();
      return(ERR_LORA_HEADER_DAMAGED);
    }

Ref: https://github.com/jgromes/RadioLib/pull/111#issuecomment-725713815 https://github.com/jgromes/RadioLib/issues/200

engeen-nl commented 2 years ago

Nice find! However, how do we implement this in the current LoRa.cpp? Can we add another condition on line 237?

if ((irqFlags & IRQ_RX_DONE_MASK) && (irqFlags & IRQ_PAYLOAD_CRC_ERROR_MASK) == 0) {
    // received a packet