USB Host Shield for Google Android ADK for Arduino Board

What is an USB Host Shield?

Before we start, let’s first understand what is an USB Host Shield. It is a shield which provides USB Host support for Arduino.



So, what is USB Host support? The USB protocol defines two types of devices. One is called the host (or server) and the other one is called peripheral (client). The Host device controls the peripheral device and also provides power to it. When you connect any USB device like a mouse or a keyboard to your computer, your computer acts as the host and controls (or polls) the client device (keyboard or mouse or even an Arduino). For a successful communication to happen using USB protocol, you need at least one of the device to be the host, which means that you cannot connect two keyboards together and expect them to communicate with each other.



The USB Host shield has a separate chip (usually Max3421E), which provides USB Host support. Once you have this shield, your Arduino board can act as USB Host and you can connect other USB devices like keyboard, mouse or even an Android phone and communicate with the device from Arduino itself.



What you can build using USB Host Shield



USB Host shield can be used to interface any USB device to Arduino. The following are examples which I have built using the shield.

- Make Android phone interact with Arduino using Android Open Accessory protocol.

- Interface a Wii remote with Arduino.

- Interface a USB Missile Launcher with Arduino.



Available Software Libraries

The following are the two libraries that are available for USB Host Shield. Both of them are from Oleg of Circuits @ Home.

- USB Host Library v1.0: https://github.com/felis/USB_Host_Shield

- USB Host Library v2.0: https://github.com/felis/USB_Host_Shield_2.0



Out of these two, the v1.0 of the library is kind of deprecated. Use it only if you really need to or have to use some other library that depends on it, otherwise use only v2.0.



User Manual Download: http://www.thaieasyelec.com/downloads/EFDV521/Datasheet_Keyes_USBHostShield.pdf



#Arduino #Shield