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LK202-24-USB Factory Restore

Posted: Tue Jul 27, 2010 7:34 pm
by b0rked
Hi,

I recently got a LK202-24 LCD screen, and was working fine.

I was using it under linux today, and I accidentally catted a binary rather than a text file file to the device. Naturally the device displayed gobbledygook, but the binary file must have contained control characters, as the device was now showing the same gobbledygook repeatedly upon startup. Any text inputted would also appear as gobbledygook, even after power cycling.

I tried to use uProject to restore the device, but I was getting no legible output from it. After a number of attempts the device is now showing no LCD output at all, apart from going black momentarily upon start up, but the backlight works fine. The device (well FTDI chip anyway) is still being detected by the computer:

Code: Select all

b0rked@b0rked$ dmesg | tail -9
[ 3306.104113] usb 4-2: new full speed USB device using ohci_hcd and address 5
[ 3306.324339] usb 4-2: configuration #1 chosen from 1 choice
[ 3306.333158] ftdi_sio 4-2:1.0: FTDI USB Serial Device converter detected
[ 3306.333214] usb 4-2: Detected FT232BM
[ 3306.333219] usb 4-2: Number of endpoints 2
[ 3306.333224] usb 4-2: Endpoint 1 MaxPacketSize 64
[ 3306.333230] usb 4-2: Endpoint 2 MaxPacketSize 64
[ 3306.333235] usb 4-2: Setting MaxPacketSize 64
[ 3306.335189] usb 4-2: FTDI USB Serial Device converter now attached to ttyUSB0 

Is there anything else I can do to fix this device?

Thanks,
b0rked

Posted: Wed Jul 28, 2010 4:16 am
by b0rked
Just to report that after jumpering the middle pins on the keyboard input I was able to set the baud rate back to 19200 using Display Tuner. I can now control the contrast and brightness, but I am still unable to write text to the device.

Posted: Wed Jul 28, 2010 10:22 am
by Clark
Hello b0rked,

It's good to hear manual override has returned at lest some functionality to your display, although it is strange to see commands but not text. I understand you are using Display Tuner, what happens when you type a text string and hit send, is there any sort of response from the screen? Is it possible contrast is set too low to see the text?

Thanks,
~Troy

Posted: Wed Jul 28, 2010 1:20 pm
by b0rked
Hi Clarke ,

Thanks for the reply.

No string appears on the display. I have also repeated that with various contrast and brightness levels but no change. What is the difference between brightness and VFD brightness out of interest?

Thanks.

Posted: Wed Jul 28, 2010 2:19 pm
by Clark
Hi b0rked,

Sorry to hear the text is still not working, if you send an email to me at tclark@matrixorbital.ca I can provide a .mem file that will restore all defaults to the unit. At this point it sounds like you've tried changing most of the settings so I'm not terribly hopeful but it may be worth a shot.

The VFD brightness command is for our VFD units only, so a VK202-24 would use this command to change the text brightness.

Thanks,
~Troy