LoRA Serial - Serial port receiving/sending gibberish

Wireless & IoT LoRa (Long Range)
1

I have the LoraSerial Kit WRL-20029 and so far I have successfully communicated point to point via USB but as soon as I try to use the serial connection it only shows gibberish as if the baud rate is wrong. However, I have set the baud rate with the AT command…I also tried different baud rates just in case. Here is the summary of what’s going on:

  • Remote device is a sensor with a serial connection at 19200bps. The plan is to send the sensor data over lora using the kit.

  • I know the sensor is working since I can use an adapter to read it from my computer just fine

  • I know the Lora connection is good because I turned on echo and I see the text transmitted

  • I set the AT-SerialSpeed=19200, saved, and restarted.

  • The data received is gibberish that resembles a baud rate error, but I am 100% positive 19200 is the correct rate

  • The sensor and the lora device share the same ground.

  • Flow control is off and not supported by the sensor anyway

Any ideas? Is it possible that the AT-SerialSpeed command isn’t working as intended?

2

Does your sensor use TTL serial or RS232 serial? If it’s RS232 it needs converted to TTL first. RS232 would produce gibberish when connected to a TTL serial device.

3

darn I did not realize the LoRa device was TTL. That makes total sense though.

Maybe I can use one of my old arduino boards to translate…or just buy a $5 cable from amazon.

Thank you!

4

Sparkfun has a converter that will do the conversion for you, it’s BOB-11189.

https://www.sparkfun.com/products/11189

A hookup can be found below.

https://github.com/SparkfunTechSupport/ … hookup.jpg