Please note that while using the IBN_ISR it is necessary to follow a certain sequence. For your convenience, it has been listed in the sequence below:
1) Disable all the other IBN interrupts by setting IBNIE to 0. You must then determine the source of the IBN interrupt by checking the appropriate bit set in the IBNIRQ register.
2) Clear the global USB interrupt flag in USBIRQ. Clear the source of this interrupt in the IBNIRQ register. Finally, clear the IBN interrupt flag in the global IBN interrupt flag NAKIRQ before exiting the ISR.
Please also note that we provide an example project which demonstrates the implementation of the IBN interrupt. After installing the CY3681 development kit software, available on our website, you can locate this example in the following directory on your computer: