I Can't uart0-communication using 96boards sensor

I tried to do uart0-communication from DB410 to other equipment via 96boards sensor.
DB410 uart0 output is no problem.(measure point :DB410_J8_5pin(UART0_TX) - 1pin(GND))
but 96boards sensor output is added fixed sentence(“Received character”).(measure point:Sensor_P2_2pin(PD1_TX) - P3_6pin(GND))

I can’t communicate with other equipment due to fixed form sentences.

How can I prevent the addition of fixed form sentences?
(Do I need to change the ATMEGA328P program on 96boards sensor ?)

If you want to use the 96boards-sensor board as a level shifter for UART0 then you will need to make sure the AVR TX pin isn’t in push-pull mode, otherwise it will interfere with your device’s own TX pin.

I would suggest writing a program for the AVR that explicitly sets the PD1 pinmode to input to avoid any problems here.

Hi danielt:

Thank you for your advise and It was nice to know the solution.
As you say, I just wanted to use the 96boards-sensor board as a level shifter.
so I will try to an write AVR prgram.