To provide a data processing device in which a plurality of CPUs can individually and independently communicate with different functions of a USB device using a single communication path. The data processing device is configured so that a USB host module to be coupled to a plurality of central processing units has a plurality of pipes to communicate with an arbitrary end point of a USB device coupled from the outside of the data processing device, the data processing device also includes an access control register to specify which central processing unit should have a right to control the pipe and specify to which extent a range of the content of setting of a function for the pipe should be allowed, and a USB host interface is controlled in accordance with the content of setting of the access control register.