CFA634 display cleared on reading USB stick


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I have a CFA634 USB connected to a powered USB 2.0 hub which also serves as host for a USB 2.0 stick. When reading the USB stick often the CFA634 clears the screen. It is as if the hide display command has been sent.

Is it possible that the display reacts on arbitrary commands that are used to control the reading and writing of a USB stick?

I use this display under Windows XP Pro SP2 and control it with a piece of C# code. Nothing fancy.
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CF Tech

In theory, the USB is addressed. The USB stick should only get commands addressed to it, and the CFA-634 should only get commands addressed to it.

There might be something weird with the hub. Power or something.

Does it only happen if both devices are in the hub? What if one, the other, or both are plugged into motherboard connectors?
USB LCD Displays - Graphic and Character LCDs with a Keypad


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I'll try that next time I'm at location. In theory it should work, because the hub is certified by the standards organisation, meaning that it also applies to the power specifications made for USB 2.0.


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Apparantely the certification of the hub is not a guarantee that it works. Without hub there are no problems, so I'll connect it straight to the usb ports on the pc.