Most recently, I bought myself an inexpensive tablet on Windows ONDA V820W. Who is interested in the video reviewer:. Well, I ran into the problem of connecting external devices. Such as keyboard, mouse and flash drive at the same time. After all, the tablet has only one OTG connector micro USB... Which is also used to charge the tablet. And since Windows still eats more than android, the issue of using one connector for several devices has become quite acute.
Having searched the site w3bsit3-dns.com a little, I found a solution with which the users of this tablet solved this problem.
This solution turned out to be a micro USB OTG hub, which has 3 outputs for external devices. It is hooked up to the tablet via micro USB and plus can also charge through the 4 input from charger the tablet itself.
Without thinking twice, I looked for a similar device on aliexpress, well, I found it for a not very expensive price from one of the Chinese. Accordingly, I ordered and after a little more than 20 days I received such a black bag.
The package is large, and the device itself is small enough, why was it necessary to put in such a huge mystery for me who would understand these Chinese :)
Well, inside the black bag, the OTG hub itself was dangling, packed in a small blister. 
On the back of the package, a picture of how to use the device is drawn and a small instruction is given in English: 
Here, in principle, everything is clear, and you can immediately see what can be connected.
Let's take a look at the hub itself: 
Everything is as stated here, 3 inputs for external devices, one for a charger, and an output for connecting to OTG.
On the side of the hub there is a switch for 2 operating modes: 1- charging mode (Charge), 2- OTG mode. 
According to the seller, in OTG mode, the hub simply works as a splitter for several USB devices.
In the second mode, the hub can take power from the input, with the charger connected, and charge the tablet.
But he immediately made a reservation that not all devices can work with this hub simultaneously both in the device's Charge mode and in the hub mode.
We will check this next.
Connector micro usb long enough and clearly fixed in the mating part. 
View of the hub entrances: 
Bottom view: 
We connect the hub to the tablet and insert several flash drives, a mouse and a charger into it for testing.
Switch the hub to OTG mode. 
On Windows 10, everything was determined and it worked fine. In the mode OTG tablet not charging.
If you switch immediately to Charge mode, then all USB devices instantly fall off. In the photo, the mouse cursor disappeared: 
But the tablet is charging.
As practice has shown, USB devices in Charge mode will still work. But for this you need to reboot Windows with devices connected to the hub and Charge mode on.
In the photo, the mouse cursor appeared: 
But in operating system android 4.4. on the tablet, this trick did not work and the devices did not work in this mode of operation of the hub.
The hub itself is defined by Windows 10 as universal USB hub: 
Now let's try to copy from a USB flash drive connected to the hub to a working one windows table 1 video file and look at the copying speed: 
As we can see, the speed is very low and fluctuates constantly around 1MB / s. Which is very frustrating, since the device itself is not bad, but with the transfer rate, everything is completely sad here.
Now let's try to copy from one flash drive to another via the hub: 
Here the speed drops even more and by the middle of copying, as practice has shown, it can generally drop to 450 kb / s.
Let's try to connect an external hard drive via the hub, I have 2. One from WD, the other from Samsung.
Samsung is older and eats almost a whole ampere when spinning up.
We connect WD with USB 3.0: 
Winchester after reboot determined: 
But when trying to open it, it first thinks for a long time: 
And then he writes that the device is not ready and sometimes even starts to click, there is clearly a lack of power: 
Well, Samsung with USB 2.0, as expected, did not even decide: 
Thus, hard drives cannot be connected, even with power from a normal Blitzwolf charger, which is capable of delivering 2.4A. 
Let's try one more function - let's see how the hub can deliver the charge current to devices connected to it in different modes.
Hub in Charge mode: 
The phone charges like a regular USB port.
Hub in OTG mode: 
The phone continues to charge, but not from the charger through the hub, but from the tablet battery.
I will add a photo of the hub's insides:
With the cover removed 
First side 
Second side of the board: 
As you can see, the Chinese saved on details and did not deliver something. Perhaps that is why the speed is low.
Well, now a video version, where you can see how the hub works with your own eyes and see my experiments with it:
Let's summarize:
1. The hub corresponds to the characteristics declared by the seller and performs its functions, all devices declared on the page are working.
2. Further more sad. The data transfer speed is very low and will not allow working directly from a flash drive connected to the hub, for example, video will slow down terribly, especially in full hd. But perhaps it will still be possible to work with the documents.
3. Devices with high power consumption, such as hard drives, refuse to work, tk. the port is not supplying the current they need.
4. Still, some devices can be charged, as an example, my phone.
5. Not all devices will work in Charge mode.
Let everyone decide for themselves whether or not to buy a hub. Well, for my needs, even with all its drawbacks, it is quite suitable, and it’s not so expensive that it’s not worth trying.
And thank you all for your attention, and what you have read to the end :)
If you look at any price list and skim through the descriptions of the PDA, then in most of them you will find a line stating that the device supports USB. This is not entirely true.
The point is that the USB installed in your desktop computer and the USB supported by most mobile devices are completely different things. In the first case, this is a USB host, that is, a board to which other devices can be connected. In the second case, the connection to the device of peripherals is not supported, the port works only "for output".
In some PDAs, developers also build in a full-fledged USB host, which greatly expands the capabilities of the device. Imagine a keyboard connected to a PDA. Or a mouse.
Previously, this feature was available only for hi-end PDAs, but gradually it appears in cheaper models as well.
USB (Universal Serial Bus) implies that the devices to be connected are unequal. The plug-in is called the "client", and the one to which the connection is made is called the "host".
For example, a PDA connected to a desktop computer is a client. But in conjunction with the keyboard, the handheld already acts as a host.
In order to make friends with a mobile computer with numerous accessories, you need a special cable - often there are two branches at one of its ends. One has a client connector, the other has a host connector. For example, this is how the cord that comes with the Fujitsu-Siemens Pocket LOOX 720 looks like. One cable instead of two is a very convenient solution. Its only drawback is its excessive bulkiness.
| Mice | |||
First place: Dialog SO-13SU Smart Mini OpticalTo be honest, it is very difficult to find a mouse that is better suited for use with a PDA. We didn’t like one of the contenders for the first place (very ergonomic) for its price (you’re unlikely to agree to pay $ 50 for a manipulator for a PDA), another had a terrible design, and the third refused to be powered by a mobile PC at all. Dialog SO-13SU We liked it right away: under the unpretentious surface there is a good "filling" - the resolution of the mouse sensor is 800 dpi. Finally, we were conquered by the price of the device - in Moscow stores it costs no more than $ 6. In general, you can always carry such an accessory with you in your breast pocket without fear of losing, breaking or forgetting - after all, even a second purchase of the device is unlikely to hit your wallet hard. Second Place: Genius NetScroll + miniTraveler Pro Optical USB
A good portable mouse deserves a "Mouse Silver" miniTraveler Pro from Genius. The only thing that prevented the accessory from becoming the first is a relatively high price, because the “golden rodent” from Dialog costs at least three times cheaper than a Genius product. Fortunately, the device justifiably pays for this money with a couple of interesting design solutions, which the Dialog manipulator was deprived of. So, the mouse is equipped with a very convenient tape measure, which hides a USB cable. As a result, wires do not get in the way of a bag or pocket and do not get confused with the rest of the belongings. The mouse is also very ergonomic and is based on an optical sensor with a resolution of 800 dpi. Third place: Blaze BL-0222 Mini Optical (800dpi) USB
Perhaps this device is a little more eccentric and ambiguous "shadow" of the previous, silver, prize-winner. They are similar in many ways - the same good optical sensor, the same coil in which the wire is hidden ... And our attention was attracted by the pleasant appearance of the device. It is, as you can see, transparent. While this has no effect on functionality, many may like the original design move. The accessory is also good at a slightly lower price compared to the device from Genius - the ultra-compact Blaze product will cost you no more than $ 15. |
Rodents
So, our task is to connect the maximum number of devices to the pocket computer that can expand its functionality.
Let's start with the mice. First, connect the “tailed” manipulator to the USB port of the handheld - it is strongly recommended to disconnect the device from the desktop PC: there may be a number of problems related to the peculiarities of the power supply board on the mobile computer. By the way, the mouse consumes a small amount of power, and there should be no problems with the connection.
After that, you need to install special HID-drivers (Human Interface Driver) to work with the manipulator - they can be found on the MOBI disk. After installing the drivers, be sure to restart your PDA.
Next, you need to pretty much dig into the registry, and for this you also need specialized software: for example, the author used Resco Explorer... So, start the registry application of your choice, open the branch HKEY_LOCAL_MACHINE and follow the address / Drivers / USB / LoadClients / Default / Default / 3 / Generic_Sample_Hid_Class_Driver... Here you will need to make a few significant changes (alas, the drivers are rather crude, so you will have to dig into the system). Create new parameter registry type String, in the graph Name indicate PreFix(be sure to respect the register!), and in paragraph Data put HID... That's not all: you also need to create a parameter DWORD by setting in the graph Name meaning Index, and on the menu Data - 1... Save your changes and reboot the handheld again.
Ideally, after a reboot, the mouse should start working, but the cursor may not be visible. The reason is simple: it merges with the interface. You just need to change the color of the cursor. To do this, open system menu Settings, then click on the tab System and click on the shortcut Mouse pointer... A window will open in which you can change the color of the pointer.
There are also known cases when the mouse managed to "slow down" - the problem, again, is rooted in the incompleteness of the drivers. If such a nuisance suddenly arises for you, we recommend that you change the processor operating mode to Normal or, as a last resort, Turbo- HID sometimes refuse to be friends with a processor operating in automatic mode.
Logitech products have always stood out from the competition with stylish design. Here and here - as soon as we saw this accessory, its fate was decided. First place.
It is a full-size keyboard with very comfortable soft buttons that have a pleasant response; Logitech UltraX even thinner than you might imagine and will fit easily into any backpack, any bag, any package, providing comfortable work with text anywhere in the world.
The main disadvantage is the high price. Logitec-style happiness will cost you $ 27.
Second Place: BTC-6100C Mini Ultra Slim Multimedia USB
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Stylish, thin, compact, comfortable and inexpensive - these are perhaps the five adjectives that best characterize the "silver" keyboard in our review. According to the arrangement of the keys, the device is the essence of an ordinary laptop keyboard: no number pad and small cursor keys.
However, it is so pleasant to work on it, and the keys have such a soft response that it is absolutely impossible to resist this accessory.
The gloss of white transparent plastic is pleasing to the eye, and the price is sparing - only $ 17.
Third place: BTC-6300C Ultra Slim Multimedia USB
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At first glance, the "older brother" of the above BTC-6100C and the "silver" keyboard itself looks like twins. However, it all ends with the external similarity.
Accessory BTC-6300C, which has received a well-deserved third place from us, is a full-size, comfortable and stylish silver keyboard, quite thin and not particularly wide - it can be easily placed in a travel backpack.
The buttons are quite "desktop" size, they are very soft pressed - typing large texts is very, very convenient.
The only drawback is the decent length of the keyboard. And, of course, the device simply cannot be cheaper than its younger brother - not the most greedy sellers will ask for BTC-6300C $24.
Keyboard boards
Almost all PDA users need an external keyboard from time to time, but sometimes there is not enough money for a special "pocket" keyboard. A convenient external keyboard of a "laptop" format costs about $ 20, which is several times cheaper than a similar mobile keyboard, which is often quite inconvenient to use.
There are several programs that allow you to work with a handheld device with a USB keyboard without any problems. However, for users who need to enter text in Russian, only two are suitable: Interkey for Portable Keyboards, from domestic developers Paragon, and AE Keyboard... These utilities have almost no drawbacks. Rather, the lack of Interkey just one - you have to pay for it. BUT AE Keyboard is a good free alternative.
After installing the program, a window with settings will open on the display. Here you can specify the keyboard layout (the program supports a bunch of options), reassign the key responsible for switching languages, or set additional Shift and Capslock- this will be especially convenient if you are using the above-mentioned "notebook" keyboards.
After launching the program, it displays the current layout in the lower left corner of the screen, however, we prefer to attribute this to the disadvantages of the driver - the constantly glowing popup could be replaced with a much more convenient indicator by top panel(as it is done, say, in the driver of "mobile" keyboards Uniboard).
After installation and configuration AE Keyboard be sure to restart your PDA. And in any case, do not disconnect the keyboard from the handheld if you do not want the program to jam. After rebooting, try out the connected keyboard - if you did everything correctly, it should work.
In the portable market hard drives own favorite has appeared, giving odds even to many "full-fledged" hard drives. His name is. There are several variants of this wonderful portable disc available. So, we literally fell in love with a 100 Gb model, which, in addition to USB 2.0, also has IEEE 1394 interfaces on board, coupled with PS \ 2.
The magnetic filling is packed in a stylish anodized aluminum box, and for carrying hard disk a special case is supplied with it.
All products of the line are extremely reliable, fast, convenient - absolutely no failures or freezes were noticed while connecting this carrier to the PDA. The only, but at the same time, quite significant drawback of the accessory is its high cost. in the maximum configuration will cost the user $ 365.
Second Place: Fujitsu USB2.0 HandyDrive Data Edition 100GB
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This mobile hard drive from Fujitsu is somewhat similar, but much simpler. It operates at slightly lower speeds, is powered by two USB ports instead of one, and the body of the device is somewhat unattractive - it is finished in gray aluminum.
Here you will not see the luxury of IEEE 1394 - you can only connect the device to a pocket or desktop computer using USB. However, this hard drive costs less.
A reliable and convenient 100 Gb mobile hard drive can be purchased for as little as $ 262.
Third place: Seagate USB2.0 Pocket Hard Drive 5GB
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When looking at Pocket hard drive from Seagate, the unusual design immediately catches the eye. The mobile hard drive is not made in the form of a parallelepiped (like the rest of its brothers), but in the form of a ball.
The compact size of the accessory allows you to easily put the 5-gigabyte wonder even in the breast pocket of your shirt.
I was pleased with the high speed of reading data from the carrier - the disk spins up to 3600 rpm and allows transferring 4-7 megabytes of information per second (there is also a 2-megabyte buffer here).
The price of the device can hardly be called "biting" - you can get a ball with five gigabytes for $ 139.
Winchester well lubricated
You probably know about portable hard drives connected to a computer via USB. Such a drive will be useful not only for the PC user, but also for the owner of the handheld. Often this device is even more important to him.
A portable hard drive can store dozens of movies, thousands of MP3s and millions of documents so that they can be opened at any time right on the PDA.
If your handheld is equipped with a USB host, connecting an external storage device to it is nowhere easier. You just need to connect the two devices with a cord, and the system will do the rest itself.
Although there are still cases when people using mobile hard drives with their PDA complain about problems. For example, the device may sometimes freeze, slow down, and so on. If you are faced with such troubles, be sure to install a program on your handheld called USB Mass Storage driver and restart the machine. Failures will stop immediately.
The choice of mobile hard drives is very wide - there are both expensive models with a capacity comparable to stationary HDDs, and cheaper models that cannot boast of a serious amount of memory.
The three hard drives that will definitely work out the money spent on them are presented in the information block "Storages".
| Concentrators | |||
First Place: TRENDnet TU-700
Now users have access to a huge number of USB hubs of completely different types and properties. However, not all of them are one hundred percent suitable for use with a PDA - one is too gluttonous, the second for some reason fails, and the other does not want to turn on at all due to the insufficient amount of energy supplied to the port. But he showed himself from the best side - without any problems connected with both powerful and weak handhelds. And numerous USB peripherals were easily connected using as many as 7 USB connectors installed on the hub. I was especially pleased with the rather stylish design coupled with the low weight - the blue box will pull your pocket back by exactly 114 grams. And, of course, for $ 27 - that's the amount you'll have to pay for a hub. Runner Up: TRENDnet TU2-700
Actually, this device is the heir to the above-described hub - in every sense of the word. First, an updated version called TU2-700, is also capable of connecting up to seven different accessories to the PDA, however, this model has a built-in external block power supply, which allows even very energy-hungry devices to be connected via USB. Actually, this is the main "update" of the model. Although one cannot but pay attention to the slightly changed design - the box has become much more compact and attractive. Retailers want about $ 45 for this product. Third place: MSI SH-101
MSI has never had a problem with device design. As conceived by the developers, even such a tiny little thing as a USB hub should be stylish, original and convenient. It really turned out to be almost the most unusual and interesting USB hub of all the existing ones on the market. Four USB port-host and one USB-client connector are packed in a wonderful-looking glossy white box that reminds all editorial staff of a mock-up of a flying saucer. The gadget works on USB interface 1.1 and is capable of transferring data at a speed of 12 Mbps. In this case, the hub is equipped with a 1-meter cord to hide. The really democratic price of the device finally finishes off - a gorgeous and stylish hub can already be purchased for $ 10. |
Concentration
The very possibility of connecting various peripherals to the PDA is good news. But there is only one USB port on the handheld, and you don't want to choose between a keyboard, a mouse and external storage, and connect both that, and another, and the third. How to be?
It's simple. Put some money in your wallet, go to your nearest computer store and buy a USB hub there.
This magical device will add up to seven additional USB ports to your PDA. The thing is not just useful - it is absolutely irreplaceable. Moreover, these pieces are most often very compact and easily fit into any bags and backpacks.
Fortunately, you do not need to install and configure anything to connect and work with them, but you need to approach the choice of a hub quite seriously. So, it is useful to determine not only the number of ports you need, but also the presence / absence of an additional power supply for the hub - it will certainly be needed if you use devices that require powerful electrical power supply.
Today, many of the most varied (often expensive) high-tech equipment is equipped with this function. Its existence seems quite logical, but it has been repeatedly forgotten and recalled by users again.
One of the leaders of the modern market of tablets and mobile devices are devices for Android... Today, this platform is once again at the peak of popularity, and we do not need any additional adapters and cables to connect USB. If there is no built-in USB, it is recommended to use USB OTG, or a regular micro-USB adapter.
USB host on a tablet: what is it?
In fact, the word "host" means any device, as well as a node / server connected to a local or global network... If we are talking about a USB-host, its presence allows us to connect an external HDD, flash drive, camera, card-reader, etc. It is noteworthy that it is also allowed to connect an external keyboard and mouse.
If the device has a built-in USB-host function, then its feature is the presence of special software (including drivers) and a USB port. This allows us to interact with other devices on our tablet - for example, copy files, or use an external mouse connected. In addition, we will be able to connect a so-called USB hub to our equipment, similar to network tees. It is inexpensive, but it allows you to make 2-4 new ones from one port.
Unfortunately, the mere presence of such a function as USB-host does not guarantee its correct operation. For example, due to the absence of any one driver, we will not be able to work with a camera connected to a tablet. Even before purchasing equipment, it is advisable to make sure that such a function is implemented with sufficient quality.
So, we found out what a usb host is on a tablet. Now let's talk about USB OTG. In fact, this function is a more modern kind of USB-host.
USB OTG as a kind of USB host on a tablet
Today, many devices with this function can be found on sale. Sometimes it even seems that USB OTG has recently been found even more often than USB-host. How do they differ from each other? The first function assumes the absence of a separate full-fledged USB port. If we want to connect an external device, we can use the mini or micro USB port.
In fact, USB OTG combines the functions of connecting to a PC (device) and USB-host (peripherals). At the same time, to connect the tablet to any external device you will need a special adapter. It is easy to purchase it online. Unfortunately, like USB-host, the USB OTG function does not work correctly on all devices - in particular, if special software is not installed on them. Also, it is not always possible to connect external hard drives.
