Hi all, I am using stellaris LM3S9B96 micrcontroller for my project. Using my own board and CCSV4.2.4.00033 . Power to my board is supplied through USB. I am using the USB for my project. I am able to handle USB EP0 traffic during enumeration and USB EP1 during data transfer. Problem is first my code runs perfectly and obtaining its functionality. When i remove USB B cable from the board and reconnect and running the code then FAULT ISR occurs. Temporary ly i am overcoming this issue by running usb_dev_mouse example given in stellarisware before dumping my code. I am handling only USB EP0 And USB EP1 interrupts. How to handle the power disconnect or handle disconnect issues. My handler is as follows. void USB0DeviceIntHandler(void) { unsigned long ulStatus; unsigned long ulStatusControl; unsigned long * ptr; //EP0 STARTING ADDRESS ulStatus = USBIntStatus(USB0_BASE); switch (ulStatus) { case USB_INT_EP0: ptr=0x40050020;//Ep0 fifo starting address data[0] =*ptr; data[1] =*ptr; EndPoint0Handler(); break; case USB_INT_DEV_IN_EP1: EndPoint1InHandler(); break; case USB_INT_DEV_OUT_EP1: EndPoint1OutHandler(); break; } } Please help me on this. Thanks & Regards, Mah Kon