Access Nuttx Shell using serial port

HI,

I’m trying to access Nuttx shell using serial port, I’m using screen with 57600 baud rate , 8N1 .
However the moment i connect, i receive arbitrary output from the serial port rather than the shell,
I have tried to remove the SD card to see if it will change the output, but it still the same.
Does anyone have an reported this kind of problem.

Best regard.