Unknown USB Device connected?

[Byra]

Im using the MQX USB Device library with a 52259. With most Windows computers, it enumerates correctly and Windows recognizes it as a CDC device and it works. However, on some computers, Windows reports "Unknown USB Device connected", and there is nothing I can do to get it to enumerate or work at all.

This happens on WinXP, Win2000, and Win7 computers. Some work, some dont.

Ive tried upgrading from MQX 3.6 to MQX 3.8 to no avail.

Has anyone else seen this and figured out how to fix it?

Thanks for your help,

Byra

[timias]

When it happens to me ( Coldfire MCF51 and K60), one of two things is usually occuring.

1. I don't have the driver installed, which can be found in <your MQX path>usb\device\examples\cdc\virtual_com\inf

-or-

2. The device is booting up in BAM mode, which is a hardware driver that resides on some chips to allow firmware upgrading. I think the driver install can be found on this website somewhere, but I have never used it.

(This is usually the result of the hardware registers not being set correctly ).