@patrickl That's indeed what I would do: just "interconnect" the UART connected to the Pi with the LTE's UART, sending data receiving from one end to the other and vice versa. Then the modem will look like it's directly connected to the Pi. Just don't call LTE and make sure you have the same speed settings everywhere. An alternative would probably to do it over BLE, but that seems like quite some more work to me.

I would try to monitor the length of the output queue. See _io_thread_func in MQTTMsgHandler.py - in there there's the transmit loop and you could add some signaling there to indicate the TX queue is empty. You'll probably need to modify the code and rename the function so you are not using the builtin frozen ones.

@elizar Thank you for confirming this!

@camdenkrupala You can already set an APN manually by doing lte.send_at_cmd('AT+CEREG=2') time.sleep(2) lte.send_at_cmd('AT+CFUN=1') time.sleep(1) lte.send_at_cmd('AT+CGDCONT=1,"IP","YOUR_APN_HERE"') time.sleep(2) while lte.isattached() == False: time.sleep(1) lte.connect() while not lte.isconnected(): time.sleep(1) print("connected")

Ill be testing with a neo-6 GPS module soon link. LoRa will be used to send the coordinates. (we will also try something like Geo-LoRa or trilateration with LoRa, but don't expect the accuracy to be anywhere near that of GNSS solutions). The metal is probably going to block the signal in your case, but ill let you know how sensitive it is.