634 USB boot problem


New member
I have a 634 usb display, and when I boot my computer crystal control cannot find the display, (msgbox "init of com4 failed")
I tried re-installing the LCD drivers, and this did not help. If I unplug the usb cable for the lcd, and then plug it back in it works. While this is a work around, I dont want to have to do this every time :)


p.s. This problem started randomly, it was working fine up untill a few weeks ago. =/
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CF Support

Any chance you've applied any patches to Windows? I would check to see which com port windows thinks the 634 is on *before* you unplug it and reinsert it.

If that doesn't make much sense, change the LCD to com 3 in Windows and see if it changes anything.
USB LCD Displays - Graphic and Character LCDs with a Keypad