I want to make communication between tablet and a SoC. For this the tablet must support USB Host Mode APIs. As per Android.com, any android device having android version 3.1 or above should support it but in reality it’s not true. Tablet manufacturers may have their own implementation too. So before buying a tablet I want to be 100% sure that the tablet I’m buying supports this functionality.
I am particularly looking for some popular western tablets like Samsung Galaxy Tabs, Acer Iconia Tabs, Sony Tabs …
If anyone can confirms that this XXX tablet supports this facility, can he also test it with usb sample application or provide some links. It would be so generous of him.
So I tried things out today,
MTP & PTP
Connecting tablets to each other:
it seems that connecting the nexus 7 with for example my Mediapad (with mtp enabled on the mediapad), does not work at least not for FX file explorer it does not show any usb storage for example. This is because I think FX explorer has no build in mtp support.
Set up example:
When turning on ptp instead of mtp the nexus automatically opens the gallery app and shows all the images from my mediapad. So android supports reading ptp devices as well as pretending to be a ptp device. But we can’t say the same about mtp, because android can’t read mtp devices or at least the app I used couldn’t. But connecting a android device to your computer using mtp works off course.
I also tried this visa versus so reading the nexus files, the same results.
When connecting a phone that does not support mtp to my tablet(Mediapad) things work out fine, the file explorer on my tablet finds the connected usb device.
Using keyboards and usb sticks
Reading usb sticks, keyboards, hubs etc works for the Mediapad.
The same for the Nexus 7 but I did not get usb sticks working on FX file explorer may be because of the fact I don’t have the full version of the app on that device.
It’s late here in Holland, tomorrow I will get the full version and try it out again cause it seems that it should be possible.
USB according to the developers site
So I started reading the USB developers guide, as far as I can tell I think reading a mtp device from another android tablet should work, but you will have to build the code for it your self.
At the moment I don’t have much time to do any more research, but in the feature I will eventually try it all out my self with some coding.
A small conclusion:
Reading another tablets files when the tablet you want to read only supports MTP mode is not possible by default, but it could be made possible using the usb api.
Reading usb devices using the host mode works fine for the Mediapad and for the Nexus 7 so far. For the Mediapad I’m 100% sure, and for the Nexus 7 because I don’t use it that often 99%.
Not sure if this if what you wanted to know, but I really hope you can do something with it. And I hope some more people will be interested in this topic and post there thoughts on it. I’m not really a usb developer my self so its all kinda new for me to, and I hope my poor dyslexia-hollandia English will not ruin your day 😉