Debugging USB Firmware Tips and Tricks for Developing USB Devices

摘要

After writing firmware for a USB device, you must be prepared to debug it. But how? The process will go more smoothly if you have an understanding of USB's layered communications, data transfer types, device classes, and enumeration. you've written firmware for JJL your USB device and are ready to test it. You attach the device to a PC and the hardware wizard announces: "The device didn't start." Or, the device installs but doesn't send or receive data. Or, data is being dropped, the throughput is low, or some other problem presents itself. What do you do?