We're using the GLK19264-7T-1U USB LCD in an embedded application, and while most are working we are seeing problems with some. Once the problem is encountered it will not clear by itself, but has only been cleared by reloading a saved copy of the original filesystem image using MOGD#.
The problem is that the display becomes permanently garbled and the boot logo nor any text that we write to the device will display correctly. We know the device is still communicating because we can use our software (running on the connected pc) to control brightness and contrast.
See the attached photo for a pic of a working LCD and a garbled LCD showing the same graphics/text.
Any and all ideas on this welcome, given we would really like to get to the root of this problem or will be forced to change LCD products for our application.
Thanks.

Hello Dave,

I appreciate the information provided, I understand you are occasionally experiencing filesystem corruption within some of your GLK19264-7T-1U units. There are two ways of locking down the filesystem to prevent unintended changes which you may want to explore.

The first is a software lock using the Set and Save Data Lock function detailed in your manual; the filesystem lock is level 5.

The second is a hardware lock, which will require that a 0 ohm resistor or jumper be placed on two pads near the 8 pin external EEPROM located using page 7 of your manual.

If you have any questions regarding either method please don't hesitate to ask.

Thanks,
~Troy

Thanks Troy,

Can you tell me why a problem like this would occur? I am going to restore this corrupted unit and try to lock it, but I also want to make sure that I can try and make sure that the code we're using to drive the display is not causing this corruption, so any ideas on how this might happen would be helpful.

Thanks,
Dave O

Turns out that reloading the unit does not fix the problem on the most recent occurrence. I've seen this problem on one prior unit, and reloading it did fix the problem. However on the current unit I'm having problems with, reloading had no affect. The display of graphics and text is corrupted, but the commands to change brightness and contrast are functional so it seems that comms is not the issue.
Seeking other ideas on what the cause may be, and how to fix.

No worries Dave,

Unfortunately, it sounds like there is more wrong with that unit than just corrupted fonts and/or bitmaps. I'd like to bring that unit in here to have a look, please provide the serial number (##M##-####) and your shipping information via PM so we can get started on an RMA.

Thanks,
~Troy