sx127x lib receive transmit problem

[davefes]

Using lemarvia's LoRa lib https://github.com/lemariva/uPyLoRaWAN
I can receive on one device and transmit on another. Now, I want to receive on one device AND then transmit a response back. However, when I do lora.read_payload() then the required processing, when I try to send a message back using lora.println(payload) it hangs. I have looked at some LoRa pingpong examples and don't see that anything else that is required.

Traceback (most recent call last):
  File "main.py", line 1, in <module>
  File "LoRa_slave.py", line 364, in <module>
  File "LoRa_slave.py", line 358, in <module>
  File "LoRa_slave.py", line 184, in process_rx_msg
  File "sx127x.py", line 215, in println
  File "sx127x.py", line 180, in end_packet
KeyboardInterrupt: 
MicroPython v1.20.0 on 2023-04-26; ESP32 module with ESP32
Type "help()" for more information.

which takes me to here:

    def end_packet(self):
        # put in TX mode
        self.write_register(REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_TX)

        # wait for TX done, standby automatically on TX_DONE
        while self.read_register(REG_IRQ_FLAGS) & IRQ_TX_DONE_MASK == 0: # --> line 179
            pass

Appreciate any suggestions.

[davefes]

Looks like you have to call lora.receive() after a transmit. See line 178

[davefes]

Thinking that the device was in standby was not correct. Looks like it is waiting for something else to happen.

[davefes]

Appears you need to call:

lora = SX127x(spi, pins = cnfg, parameters = loracnfg)

after each processing each RX packet

[davefes]

See above