USB host/HID interface

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Here is a companion device for those already using the the Webtop hack.

http://forum.xda-developers.com/show....php?t=1199443

It's the same OTG USB hub hack used with the Atrix, just wanted to share my setup and testing. So far it works excellent.

Right now, I have a USB keyboard and mouse, a FAT32 flashdrive, and a FAT32 external HDD all hooked up the the hub, and I'm watching a movie
off the HDD.

The basic theory of operation is that in micro usb connectors there is a fifth pin, actually the 4th over in a schematic. That pin is actually the ID pin, when its state changes it indicates to the phone that it USB mode is changing. In our case, we ground it, telling the phone to go into host mode. Now because the phone cant supply power to the USB device, we have the red jumper wire on the hub itself. This is effectively bridging the +5 from the power supply to the phone.

It should be noted that as of this post, i have only tested FAT32 formatted drives with this setup.
I'm working with a friend at the moment on an NTFS module, so the Photon can utilize NTFS drives.

Now, my setup looks a bit off because my connectors are on order and the one in the pictures, is one I cut out of a motorola cable. So it doesn't look pretty, but works great.

Great job!

What type of usb hub can I use? does it have to have usb 2.0 or 3.1? Does it have to have ac adapter? Can I use a usb host cable otg instead of a micro usb and does it make a difference?

Thanks in advanced!

Sent from my MB855 using xda premium

Originally Posted by jguevara4854

What type of usb hub can I use? does it have to have usb 2.0 or 3.1? Does it have to have ac adapter? Can I use a usb host cable otg instead of a micro usb and does it make a difference?

Thanks in advanced!

Sent from my MB855 using xda premium

It can be any powered hub, if you plan to use an external HDD with it you should make sure the power supply for the hub is at least 2 amps. For now its only USB 2.0, USB 3 isnt compatible. I modified a stock USB micro cable, but you can but a OTG cable that will work with this setup. Like the link below, that is a OTG adapter. Also, the hub would need a few modifications, like i was talking about at the top.


http://www.amazon.com/USB-Micro-Fema..._sim_dbs_cps_2

You guys rock

Sent from my MB855 using xda premium

Nice work.

TS

This is what I've done... not sure if I did it right. Pls run a quick look see if I did?

Thanks in advanced.

Sent from my MB855 using xda premium

Connected a phat32 hdd and mouse and keyboard non seem to work. My set up is usb to otg micro and judging from my soldering skills you can clearly see I added a white cable to jump from power to usb.

Sent from my MB855 using xda premium

You may want to check your OTG cable. If its not set up properly it will not function. The un-used pin in the micro connector must be grounded. Ive noticed not all the cables you can buy are quite right. Thats why i build my own. I hope to get up rev 2 tomorrow...a bit more in depth. Maybe i can shed some more light on the issue...

Sent from my MB855 using xda premium

Thanks for looking into this.

So, once you've mod a USB hub, are you using a cable that is <male micro USB to female USB A>?

I've not seen that before. Usually, USB cables that have a micro USB on one end will have a male USB A on the other, not a female. I did a quick search and couldn't really find any <male micro USB to female USB A> cables. I also didn't see any female A to female A cables that would allow for the same thing.

Please elaborate, thanks.

Edit: oh, maybe you use a USB 2.0 A to Micro B Female / Male Adaptor?