I am sorry for taking so long to reply. I have been away for a few days.

Yes, our circuit's ground is connected to earth ground. I cannot say for certain that this was always the case (refering to the previously mentioned problem), but I can say that it is now.

Thanks again,

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Ryan J. Allen

When the LCD was grounded to our board's ground we noticed bytes being stored in the keypad buffer, making it appear as if someone had been pressing keys. Out software, of course, could not differentiate between legitimate and "noise generated" characters.

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Ryan J. Allen

Tom, thanks for your reply.

Currently we have the ground floating. We used to ground the LCD with the digital ground on our control logic circuit board but stopped when we noticed more problems.

The LCD is mounted on our our chasis with nylon washers between the LCD and our chasis. The LCD itself ...

I am using GLK24064-25 (PCB rev. 1.3) and are experiencing problems where the display will completely lockup, with the contrast being off (usually the display is extremely dark), and a power cycle is required to restore the device to a usable state.

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