I used to write an ad for EZUSB (2131) series chip DLL. Examples are

凌阳SPCA5XX解码芯片USB驱动源代码，仅供参考，请不要用于商业用途。-Sunplus SPCA5xx decoder chip USB driver, reference only, not for commercial usage.

Usb camera frame render library

Driver modules for bluetooth using for PXA255.

USB CDC implementation on Silabs MCU

关于usbview的程序-procedures on usbview

本文档可以通过修改USB接口的用户密钥设置，可以作为生产使用

这是一个USB1.1通讯的PC机调试程序，对于usb编程的开发人员具有一定的借鉴作用。-This is a USB1.1 PC communications debugging procedures, Programming for usb personnel have developed a certain reference.

usb bulk read and write with libusb lib, it is a useful lib,it is great

usb 2.0 的规范说明。-usb 2.0 specification.

This example firmware is based on Microchip s USB Support Firmware. The purpose of this example is to provide a model for making a USB combination device. This mainly entails having the USB descriptors set up correctly. File usb_ch9.c contains the mouse and keyboard descriptors in the correct configuration. The main routine of this example moves the cursor in a circle and sends keyboard keycodes for the message "Microchip USB" over and over again. Some advice: Before running this firmware open a blank text document. Make sure that when you run the device/emulator that you are able to give focus to the document. The cursor will be moving in a circle so make sure you have plenty of room to click on the editor window. This will allow you to see the message "Microchip USB" without inadvertently having the message type over an existing document.-This example firmware is based on Microchip s USB Support Firmware. The purpose of this exampl