Strange driver prob with USB 634 & XP


New member
I'm having a *very* strange problem with the USB port driver for the 634 :(

every time I restart my comp, the only way to get CrystalControl (and other LCD s/w) to recognize the LCD is connected, is to remove the LCD from Device Manager, restart, let XP find the display and install the port driver.
If I don't go through the above procedure, when I restart, the display initializes but CC says it can't open Com 3 (as per port driver)

any ideas??
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New member
Resource Conflict!

You have a resource conflict somewhere.
I had the same problem and fixed it by messing with my hardware settings.

In my case the printer port was the problem and after I changed the setting for it in the bios all was well.

Hope that helps.
USB LCD Displays - Graphic and Character LCDs with a Keypad

CF Support

Since you're using XP, the first thing that I would try would be to edit the device settings, and change the port that it's assigned to. This will probably necessitate a reboot (MS loves the power cycle), but should fix the problem. It will likely assign it a different driver, but should function properly after that.


New member
Chepaman, I've disabled my onboard LPT port (gotta love USB printers), all onboard sound (ok, ok it already was disabled), changed the game port range to 209
disabled both COM1 and COM2 and one USB controller, it hasn't worked :(
CF Support, just changed the port driver to COM4 (and reconfigered CC) and restarted still have the same problem

I'll just go and check on one of my other XP machines and see if I still have the same prob.
btw my mobo is a Epox 8K3A+

edit: Ok if I unplug the LCD and replug it in, restart CC all works fine :confused:
edit 2: No probs with the driver on my other computer (asus A7V266-VM mobo)
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