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Android Java USB Host API not working

PostPosted: Thu Jun 14, 2012 6:39 pm
by Zauberwort
Congratulations on the great device - I got it today and love it. I have several USB based measurement devices that I want to connect to it.
While USB Host for keyboard, mouse, etc. works just perfectly, the Android USB Host Java API doesn't get any USB devices enumerated. My other ICS devices (Xperia Ray, Acer A501) enumerate them just fine and I can use the Android USB Host API for control and bulk transfers. I can see that the Linux subsystem has my devices enumerated, but they are not passed through to the Java API. Is there something I can do about this?
Thanks!

Re: Android Java USB Host API not working

PostPosted: Fri Jun 15, 2012 11:40 am
by andykirby
Hi,

have you tried looking here:

http://developer.android.com/guide/topics/usb/host.html

Haven't had direct experience with this as yet so couldn't comment more.

Thanks,

Andy

Re: Android Java USB Host API not working

PostPosted: Mon Jun 18, 2012 9:35 am
by Zauberwort
Hi Andy, thanks for your reply!
The API you link to is exactly what I meant: This API is not seeing connected USB devices on the MK 802, while on other ICS devices the API gives me access to my devices. So the problem is somewhere in the MK configuration or drivers. I appreciate your research effort, though.
Daniel

Re: Android Java USB Host API not working

PostPosted: Mon Jun 18, 2012 9:39 am
by Zauberwort
Hello MK802 fans,
I found this configuration file which is missing on the MK802: http://code.google.com/p/ics-nexus-s-4g ... t.xml?r=18
I added it, but still, no enumeration nor access to my USB devices. I'll keep on looking.
Daniel

Re: Android Java USB Host API not working

PostPosted: Tue Jun 19, 2012 7:30 am
by Zauberwort
Hi Everybody,
I tried setting the permissions in ueventd.rc for ...
dev/bus/usb/* from 0660 to 0666
... but still no enumeration of my custom FTDI based device (serial to USB controller) by the Android USB Host API.
If anybody has other suggestions, I'd be very happy!

Thanks,
Daniel

Re: Android Java USB Host API not working

PostPosted: Wed Jun 20, 2012 12:45 pm
by mgplusman
I ran into the same issue in attaching USB-to-serial adapters and performing the previous posts steps (and I still was unable to iterate the USB devices).
The issues is that ADB does not allow for other USB access while connected to Eclipse.
So when I ran my app (without a debugging connection), I was able to get the device list.

Refer to the last section of the following link, it talks about TCP connection and ADB:
http://developer.android.com/guide/topi ... index.html

Cheers