One interrupt vector is assigned to the USB interface. The following figure shows the structure of the USB interrupt system.
Figure 1. Interrupt System
See Interrupts in the Device Operation section and Interrupts in the Host Operation section for further details about device and host interrupts.
There are two kinds of general interrupts: processing, i.e., their generation is part of the normal processing, and exception, i.e., errors (not related to CPU exceptions).