635 Not Responding

Topher Fangio

New member
Hello all,

We just received a CFA-635 unit and I am attempting to test it and get it working. Firstly, when I plug the unit in via USB it powers on and appears to be working correctly. The screen is fairly bright, the top left LED is green and the LEDs for the buttons appear to be on.

Under Windows, I have installed the drivers according the the download page and it went very smoothly. The test program, however, always says "Looking for module". I have also installed CrystalControl and have attempted to use it, but it also appears to be non-responsive.

Under Linux, the device shows up when using the 'lsusb' command and Linux creates a /dev/ttyUSB0. The test program simply times out so I am now attempting to use the lcd4linux program to connect. At first, the program failed but after I downloaded the latest source and compiled it myself, everything appears to work correctly except that the debugging message shows that it cannot detect the display and all of the packets that are sent time out.

I have looked for the J2 spot on the board and it looks like it is soldered.

This looks like a great unit and exactly what we need so we would love to get this running. We are on a really tight schedule so any help or suggestions would be greatly appreciated.

Is there something that I am missing or a way to debug the unit a little bit more? Please let me know if there is any more information that I need to provide. I will be checking the forums very regularly.

Thank you very much!
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USB LCD Displays - Graphic and Character LCDs with a Keypad

CF Mark

The backlight turns on, keypad lights turn on and the top green led... but does the LCD display the boot up logo and text?

It should display this:


Topher Fangio

New member
Below is an excerpt from the confirmation e-mail which should tell you all of the information:
   * DB635BKYYEKU1
   - Includes items:
       * CFA635YYEKU1
           - CFA-635 USB LCD 20x4 +Keypad
           - Yellow/Green LED Backlight
           - STN Positive, Yellow/Green
           - Transflective 0°C - +50°C12:00
           - Includes items:
               * WRUSBY03
                   - USB-A to 2mm Cable for all USB Displays
                   - RoHS Compliant
       * DB635BK
           - Black Plastic overlay for CFA-635
Thank you for your responses and please let me know if you have any more questions or need any more information. I will check back after lunch.

Topher Fangio

New member
More Testing

I tried a bit more testing and still have had no luck. We tried on another Windows machine and when we ran the test program, the machine blue screened and died. I tried it on both machines while attached to a dock and while not attached (after rebooting) and still nothing under Windows or Linux. Is it possible that we simply have a bad unit and need to return it or is there something else that I need to do. We really need to move forward on this as soon as possible so any ideas that you have would be great. If you do believe it to be a bad unit, could you please let me know so that I can go ahead and get it replaced?

Thanks again for the help.