Hello, I'm an undergraduate student who encountered an error while running the sensor.

I referred to "https://wiki.dfrobot.com/RS485_Wind_Direction_Transmitter_SKU_SEN0482" and copied it perfectly.
However, "Segmentation fault" is output.

This picture shows the wind and RS485 in use.

This is a picture of the wiring of the RS485

I used the code without changing anything.

This is the link that contains the code.

https://github.com/DFRobotdl/RS485_Wind_Direction_Transmitter

The GCC version is 8.4.0.
Segment fault has once been executed without being displayed.
This was done by running 1000 times in a row.
But it's not good news.
Wind Direction: [null] appears until the wind gauge moves.

When the wind gauge moves, Segment fault appears immediately and the code ends.

Please give me a solution.