Serial port disconnect problem

wing_zyy

Hi, good day,
      Recently, we use armbian on orangepi zero that is connected to a 3D printer with serial port. The OS recognize the serial port as ttyUSB0 through USB port on orangepi, but the port would be disconnected automatically, after throwing "###X_Eeferencing free block". Could someone tell us if this is because of the OS and how to solve this disconnection issue?

Thank you and best wishes.
Yuan

igorpec

MicroUSB port is used by serial console by default. You need to disable getty to make use it for some other purpose.

wing_zyy

igorpec replied at 2019-12-25 16:57
MicroUSB port is used by serial console by default. You need to disable getty to make use it for som ...

Thank you for your reply, igorpec!
What you mean is the port would not be disconnected as long as getty is closed?
But at the beginning of running kermit, the port can ben connected, and the data sent by printer can be recieved by the serial port, just after running for a while , the port is disconnected, and the period is not fixed. So it is also because of getty?

wing_zyy

It seems that getty cannot be disabled, and there is not ttyUSB0.service for the serial port that is used to connect the printer.
In getty, there are three services, which are getty@tty1.service, serial-getty@ttyGS0.service, serial-getty@ttyS0.service. which ports are these service related to? which port service is related to ttyUSB0??

igorpec

serial-getty@ttyGS0.service