In order to get the phone to go into OTG mode, we need to short Pins 4 and 5. You can either choose to short them permanently by soldering them together or soldering two wires to each of the pins and leading those outwards from the connector, which can then be soldered to a small switch. Using the switch, we can switch the cable between normal and OTG whenever needed. If you choose to short it permanently, you will have to cut off the connector at the other end (The Type A Male USB connector) and solder a Type B Female connector to accommodate a USB device. You can also choose to have a male to female USB convertor at that end. Here's what we did: How to Make your own USB OTG cable for an Android smartphone
More ideas for using USB OTG (I have tried many of these with success!) Steve
From there, you can start plugging in a number of USB devices. Here are the ones I tested using the Samsung Galaxy S III (S3):
- USB thumbdrive: When you plug in a USB thumbdrive, you Android device will quickly display its contents. You can play movies, play music, and view photos or documents. The interface also allows you to move or copy files from your thumbdrive to your phone's SD card. This is the most practical use of the USB OTG adapter, and an excellent way to quickly transfer files or expand your device's storage.
- If, by chance, your device does not recognize the USB thumbdrive, try accessing it with an app like ES File Explorer.
- Desktop keyboard: If you need to do long-form writing, you can use a standard computer keyboard (wired or wireless) to type on your Android phone or tablet. Even shortcuts like Ctrl-A and Ctrl-X will work.
- Mouse: This was pretty surprising -- when you connect a mouse (wired or wireless), a pointer will appear on your Android's screen. With that, you can use the mouse just as you would your finger.
- USB hub: What if you want to connect a keyboard and mouse at the same time? With a USB hub plugged into the OTG adapter, you can do just that. Of course, your battery will drain a bit faster, but the setup might be worthwhile for power users.
- Powered hard drive: Because your Android powers whatever device it's connected to, a portable (not powered) hard drive won't work. However, a powered hard drive will, since it relies on energy from an external source. With the hard drive connected, you can read, write, and transfer any stored files.
- PS3 controller: Now, this is pretty crazy. The Samsung Galaxy S III is stock-compatible with the PS3 controller. As soon as you connect it, you can navigate the interface using the analog (thumb) stick. Most importantly, the controller is compatible with some Android games. So far, the inventory of PS3 controller-ready games has been hit or miss, but Sega games (like Sonic) definitely work.
- Card reader: Photographers will appreciate the USB OTG's compatibility with card readers. In theory, you could shoot photos on your high-quality camera and upload them on the go using your Android phone or tablet. This could also be useful for pro photographers who can show their clients previews or share sneak-peeks of photo shoots through apps like Instagram.
- DSLR camera (Canon T3i): The OTG adapter coupled with your dSLR's USB cable allows you to tether your camera to your phone or tablet. Using an app like Remote Release or DSLR Controller, you can even use your Android device as a remote shutter release, as well as control camera settings and mirror them live.
With time, more Android devices will likely support USB hosting. If you discover any additional devices that support the USB OTG adapter, or other USB accessories that work with it, let me know in the comments.
- USB-to-Ethernet adapter: If Wi-Fi isn't available, or you want a supersteady Internet connection, you can connect a USB-to-Ethernet adapter ( like this one ) to your USB OTG and connect the phone or tablet to a wired Ethernet connection.
Sharon Vaknin http://www.cnet.com/how-to/clever-adapter-connects-usb-accessories-to-your-android-device/
