The oti arc messes up transmissions on my lora module

Hi, I have a small project where I have a raspberry pi connected to a lora module.

We wanted to test the power consumption of the lora module connected to the otii arc

So we took the oti arc and clipped it on to gorund and the voltage pin of the module.

The issue now is that the lora module runs, but whenever it’s powered through the oti with 3.3 volt,
But something strange happens when the otii acts as the power supply, and it changes some of the messages that is sent, like some of the bytes are flipped or changed.

Does anyone know what this is?

Hi and welcome to the forum,

I am not sure exactly how your setup looks like, a block diagram of all the connections might help.

My assumption is that you have connected Otii Arc main to LoRa power and that you are listening to the communication between Raspberry Pi and LoRa module via an UART that is connected to Otii Arc UART TX, then there are some things you would like to check up.

  1. Is it the same GND? LoRa module GNS, is that the same as Raspberry Pi GND and your UART GND? Do you have a schematic drawing of all the GNDs?
  2. Have you set the digital voltage level to the right level?
  3. If the UART text is readable sometimes and then unreadable and then back to readable then it sound like the clock is drifting.

I hope some of these thoughts helps!

Best regards,