Dear Troy,

Thanks a lot for prompt reply.
The LK204 is connected to Arduino via RS232 and Tx/Rx pins of Arduino are used to update the program.

I did manual override.

The present state is:
i) I can change display brightness and contrast
ii) I can change the state of three LEDs and keypad ...

My LK204-7T display was working correctly and I'd interfaced it to Arduino.

Now it is not responding properly and I'm not not able to pinpoint what caused the error.

I can only change the display brightness and contrast using uProject but cannot make anything to display on LCD.

It gives one ...