Question Understanding Grove RS485 Output Signal

Hello Everybody,
i’m trying to understand this module.


I can make a communication with a device. But what i don’t understand is, why the output is not opposite symetrical as expected from RS485-Standard.
Output_Not_Inverse_Symetrical|690x65
I’m using RX and TX as Standard Serial1 on an Arduino.
What am i doing wrong?
Does an example exist somewhere?
Thank you in Advance

This is a simple UART to RS485 device.The underlying software USES a serial port. @Rookie

Thank you.
Ok i will consider it working that way.
I had expected to have a waveform at the output like this https://en.wikipedia.org/wiki/RS-485#Waveform_example and not the message on one cable but on both inverted to counteract the condensator effect on long distances.
Thanks again!