Help: CFA-633 not working fully


New member
Hi there.

I'm struggling to get my CFA-633 TMC KU panel working (bought 'new' from eBay). I've got it powered up and the backlight comes on, but it only displays solid squares for each character on the LCD display, and I don't think it's booting correctly.

WinTest and cfTest both correctly detect the display (CFA633:h1.5,k1.9), both can set the brightness of the backlight, and both apps correctly register button presses on the keypad, but neither can clear the display, or change the text output of the display.

Does anybody know what I might be getting wrong? I'm testing from my Wndows 10 laptop. Will an older operating system make a difference, maybe?

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USB LCD Displays - Graphic and Character LCDs with a Keypad