XCore Exchange

Hi all

Is there a flag to judge whether the USB device is correctly connected and recognized by pc?
2 usb midi device interface implement by xmos, i want to light one led for each usb device connection.
but i don't know how to make the judgement?

there should be some function of flag in the module_xud or some other libary for the usb. do someone know about it?
otherwise, maybe i should check usb enumeration process.,and confirm a usb's connection after host get the configuration descriptor.