Have you heard about USB OTG? This is one of the interesting features in Android devices currently. This allows USB devices like Tablets or Smartphones, to act as a host, allowing other USB devices like USB Flash Drives, Digital Cameras, Mice or Keyboards, to be attached to them. What this does is it allows those devices to switch back between roles of host and devices. There are many interesting things you need to know about this new technology. Currently, not every device supports this but also a way in which you can be able to set it up in your android phone device. All you need to know about USB OTG has been detailed for you here in this article.
One thing about the USB OTG is that it has introduced an action whereby a device can perform both host and peripheral roles, meaning that when two devices are connected together, one of them is USB OTG device, whereby a communication link is been set up. The device controlling the link is the host or master, while the other is the peripheral or slave.
What’s More About USB OTG?
One thing again you should know is that USB OTG specifies two roles for devices: OTG A-device and OTG B-device. Giving that OTG A-device is the host which supplies power, while OTG B-device is the peripheral which consumes the power. So this is a clear indication the USB OTG tries to give prior to the work of each of them. Absence of USB OTG will enable mobile phones implemented as peripherals to easily transfer data to and from computers. But one thing there is that such devices that act as peripherals cannot be connected as printers cos they’ve been assigned the slave role.
With lots of improvements been put in place, many devices can now act as either host or peripheral depending on what transfers the bus. Take a computer printer as being the peripheral, but if you plug a USB flash drive into the printer’s USB port when the computer is been turned off, then that printer will automatically serve as the host, whereby the flash drive is been allowed to communicate directly with it. Also, most gadgets must be either a host or a device. OTG hardware design merges all of the controllers into one dual-role controller that is somewhat more complex than an individual device controller.
There are about three new communication protocols been introduced by the USB OTG such as; the Attachment Detection Protocol (ADP), the Session Request Protocol (SRP), and then Host Nation Protocol (HNP). ADP allows an OTG device, which serves as host to determine the attachment status in the absence of power on the USB bus, enabling both insertion-based behavior and the capability to display attachment status. The SRP on the other hand, allows both communicating devices to control when the link’s power session is active, because only the host is capable of doing this putting the standard USB in place. Whereas for the HNP, two devices are been allowed to exchange their peripheral roles, meaning that the USB OTG device is capable of initiating data-transfer over USB OTG bus when the HNP is been used to reverse the host roles.
One other important thing that HNP does is that it accommodates users who have connected the A and B devices in the wrong direction so they can perform a certain task. For example, a printer is connected as the A-device, but cannot function as the host for a particular camera, since it does not understand the camera’s representation of print jobs. When that camera knows how to talk to the printer, the printer will use HNP to switch to the slave role, with the camera becoming the host so pictures stored on the camera can be printed out without reconnecting the cables.
USB OTG Key Specifications
There are some other labels you should know about USB OTG device. There is the Standard, Mini, and Micro USB plugs in OTG. The white areas in the drawings represent hollow spaces. As the plugs are shown here, the USB logo (with optional letter A or B) is on the top of the overmold in all cases.
The original USB OTG standard introduced a plug receptacle called mini-AB. This can accept either a mini-A plug or a mini-B plug, while the mini-A adapters allows connection to standard-A USB cables coming from peripherals. The standard OTG cable has a mini-A plug on one end and a mini-B plug on the other end. The device with a mini-A plug inserted becomes an OTG A-device, and the device with a mini-B plug inserted becomes a B-device.
There also the introduction of OTG micro plugs. With the introduction of the USB micro plug, a new plug receptacle called micro-AB was also introduced. It can accept either a micro-A plug or a micro-B plug. Micro-A adapters allow for connection to standard-A plugs, as used on fixed or standard devices.
An OTG cable has a micro-A plug on one end, and a micro-B plug on the other end (it cannot have two plugs of the same type). OTG adds a fifth pin to the standard USB connector, called the ID-pin; the micro-A plug has the ID pin grounded, while the ID in the micro-B plug is floating. A device with a micro-A plug inserted becomes an OTG A-device, and a device with a micro-B plug inserted becomes a B-device. The type of plug inserted is detected by the state of the pin ID.
Also, when an OTG-enabled device is connected to a PC, it uses its own USB-A or USB Type-C cable (typically ending in micro-B, USB-C for modern devices). When an OTG-enabled device is attached to a USB peripheral device such as a flash drive, the peripheral device must either end in the appropriate connection for the device, or the user must supply an appropriate adapter ending in USB-A. The adapter enables any standard USB peripheral to be attached to an OTG device. Attaching two OTG-enabled devices together requires either an adapter in conjunction with the slave device’s USB-A cable, or an appropriate dual-sided cable and a software implementation to manage it.
OTG Device Compatibility
There are some Smartphones and Tablets which are compatible to the USB OTG device. Blackberry 10, for instance, implemented a Host Mode such as in Blackberry Z30. Nokia has also implemented USB OTG in many of their Symbian phones such as Nokia N8, C6-01, C7, Oro, E6, E7, X7, 603, 700, 701 and 808 Pureview. HTC Android phone and Sony (Xperia) has also implemented it. Also, Samsung version 3.1 or newer supports USB OTG, but not on all devices.
In many of the above implementations, the host device has only a micro-B receptacle rather than a micro-AB receptacle. Although non-standard, micro-B to micro-A receptacle adapters are widely available and used in place of the mandated micro-AB receptacle on these devices.
In terms of the charger compatibility, some devices can use their USB ports to charge built-in batteries, while other devices can detect a dedicated charger and draw more than 500 MA (0.5 A), allowing them to charge more rapidly. OTG devices are allowed to use either option.
Can USB OTG Adapter be used on Smartphone?
Well, the answer is yes. This is because a USB OTG compatible device, which is almost on every Android phone, except the older ones which needs rooting and installation of a custom ROM, is competent to act as a controller or a host of the other USB devices. Using SD card and other card readers on a Smartphone are very common with OTG adapter. But in as much as that, there are different ways for you to use OTG adapters.
There are some certain things which you can be able to use the USB OTG adapter for.
One of the uses of this adapter is as a source of charger to other phones. This allows you to transfer the battery charge of one Smartphone to another using an OTG cable. Simply connect two phones- one with OTG dongle and other with power cable. The Smartphone connected via power cable will go in charging mode and the phone connected with OTG adapter will be the power source.
It can also serve as a Voice Recording device. That is because most digital cameras come with built-in microphones, which you can use your Smartphone’s microphone to record audio clips on your Windows or Mac. You can attach your phone through OTG and utilize the phone’s microphone to record audio via PC software. On the other hand, you can also connect professional USB microphones to your Smartphone using OTG adapter.
You can use t a source of musical instruments whereby you can compose your own music on Smartphones. Musical instruments can be connected usually with Computer via MIDI standard. Using OTG cable, you can connect your MIDI controllers to your Smartphone via USB. To use the MIDI controllers properly, you will require downloading some application like TouchDAW.
Another thing is that you can add your Smartphone is to make use of USB mouse or USB keyboard. Typing on a touch screen might not a feasible option for many. Simply attach a USB keyboard to your phone using OTG adapter and enjoy the work. You can also use a USB mouse to navigate the Smartphone and add efficiency to your daily tasks.
You can as well use other USB accessories like LED light, portable fan, etc with Smartphones when connected via OTG.
The OTG cable and a USB Ethernet connector can also be used to stimulate the home broadband connection directly to your Smartphone. All you need is to plug them both and in order to secure a wide range of connection.
You can as well connect the 3G/4G dongle with your Smartphone via OTG. But at first, you’ll need to download the PPP Widget 3 Android app from Play Store. Connect your dongle to the phone using OTG cable. Select PPP Widget to pair the device with the dongle. Enter the internet dial-up settings received from your ISP and hit the connect button and voila.
With OTG, you can equally print directly from your Smartphone without the need of a printer. There’s no doubt that the normal printing process requires a computer to give prints. You have to transfer the files and documents to PC and then print them. But now, you can connect the printer to your phone using a USB OTG cable. All you need is to install the PrintShare app on your phone and it will automatically pick up the latest drivers for your USB printers, with a simple tap on the print option on the app and it’s done.