Android ADK USB Accessory Mode/host mode

Question

I have a general and quick question and since you can never get a hold of a developer at Google, I thought I would post the question here...

Can anyone tell me, if we want to use our phones to connect via USB to a missile launcher made by dream cheeky As suggested on the USB or ADK section of the developer's website, would we still need and Arduino board or a board that Google presented at Google I/O 2011?

I guess I am asking, in short, can we directly hook our phones to another device via USB, and compile a program via eclipse or with the ADK to have it run? or will we still need a board in between the phone and the device we want to connect USB...

Thanks in advance, Richard

Answer 1

In ADK, the Android device acts as a USB Device and the Android accessory acts as a USB Host. When an Android accessory is attached to the Android device, the Android devices switches to "accessory mode (as described in ADK)". If your Android device has USB host already, still it will switch to accessory mode and acts as USB Device instead of USB Host. Actually, the motivation behind ADK is to make each Android device to work with any Android accessory. Accessory mode eliminates the need for USB host, since only few devices has USB host feature (It is costly). So, if you want to work with ADK, you need an development card with USB host.

Answer 2

you do not need an ADK board if the device that you are connecting to your Android device is acting as the USB Device and your Android device is acting as the USB Host. This is the case with the Dream Cheeky USB missile launcher. You can connect a missile launcher directly to the device and control it. USB Host is only supported on Android 3.1 devices and later.