Find out if LCD panel is connected to serial port

[madz]

I have a LK204-7T LCD panel running on a Linux machine connected to a serial com port. I am starting the LCD panel through a startup service. Is there a way to check if the LCD panel is actually connected to the machine before I run my service?

[Raquel]

Hello,

Thank you for posting on the forum.

You can check for ttyUSB0 to know when a display is plugged in.
To further confirm, ask for a module type or version number (please see commands in the manual) and check the display's reply.

I hope this helps.

Thank you,
Raquel

[madz]

I'm connecting the LCD via a serial com port (not a USB serial port) which is a 'ttyS0'. And the machine already has a 'ttyS0' in it regardless if the LCD is connected or not. My issue is identifying if the LCD is connected without having to write to it first.

[Raquel]

Sorry, I assumed you have a USB model.
Unfortunately, no there is no way of knowing a display was plugged in via the serial com port without writing to it.

Thank you,
Raquel