Simulation testing apparatus and method for embedded system based on universal serial bus host

Abstract

Nowadays, more and more embedded products are required to have capabilities of communicating with accessories or other devices through USB (Universal Serial Bus) as host. Different from USB device, the host occupies a unique position as the coordinating entity for the USB, and thus the mature methods used for USB device test do not work in USB host test. Especially, the USB host built in embedded system has special architecture and supports specified applications; thus normal USB devices in market cannot be used to test the USB host system. So how to verify the functionalities of USB host in embedded system or applications based on USB host is always a big challenge for developers. This paper presents a method to test USB host functionalities and even the entire system based on USB host. The core of the method is a configurable USB device simulator connected to PC (personal computer) and software on PC which can configure the simulator dynamically and extend functionality of the simulator. An apparatus based on the method has been developed and put to use in a real project.