[Toybox] Pocket workstations.

[David Seikel]

On Thu, 19 Jul 2012 00:34:42 +1000 David Seikel <onefang at gmail.com>
wrote:

> On Wed, 18 Jul 2012 22:28:15 +1000 David Seikel <onefang at gmail.com>
> wrote:
> 
> > On Fri, 15 Jun 2012 20:25:13 +1000 David Seikel <onefang at gmail.com>
> > wrote:
> > 
> > The main problem I am seeing right now with the "just use a hub"
> > approach is that the USB standards are against the particular
> > combination I need right now.  At least according to my
> > recollection, and a little bit of research.  More research is
> > needed.  My existing powered HUB has a mini B socket, my phone has
> > a micro B socket.  You are not supposed to hook those two together
> > directly.  In fact, I'm not so certain it's that easy to find USB
> > hubs that come with the host connector being anything the USB
> > standard says you are allowed to use to hook to a typical phone
> > micro B USB socket.  Not with commonly available off the shelf
> > components.  There are non standard USB cables, but only for
> > popular things.  This is not popular yet.
> 
> Ah I was looking at this the wrong way.  Normal USB OTG adaptors come
> with a USB type A socket, so I can plug the hub into that using it's
> normal cable.  I was trying to bypass that extra cable.
> 
> Also looks like it's theoretically possible to use USB and the MHL to
> HDMI at the same time, but Samsung have not yet released the cable to
> do that.  Might be a third party one I've not found yet.
> 
> Getting a little closer.  B-)

http://www.ebay.com/itm/Micro-USB-Host-OTG-Cable-With-USB-power-for-Samsung-S2-i9100-S3-i9300-i9220-9250-/140787406541?pt=PDA_Accessories&hash=item20c79556cd
looks promising.  I'll get one and try it.

To save you the trouble of looking, it's basically two short bits of
cable and three USB connectors.  One connector is a micro B plug for
going into any phone that supports USB OTG over micro USB (starting to
become common in high end phones and tablets I think).  That's the
standard that will do what we want, OTG means "phone acts as the USB
host".  The second connector is a USB A socket, which you can plug most
things into, most importantly you could plug most USB hubs into that.
The third connector is the missing link, it's a USB A plug for plugging
into some power thingy, like a typical USB charging wall wart.
According to the advert linked above, it can provide power to the phone
for charging, and power to the HUB for passing onto other devices.

I have seen video of my particular model of phone using OTG to connect
to hubs, mice, keyboards, sound, and storage devices using the standard
drivers that come with the phone, and not even needing to root it.

You can find hundreds of USB OTG adapters on eBay, but I could not find
any for sale locally.  In fact I could only find one other person who
even knew what OTG is here in Australia's third largest city.

That leaves video and networking.  Ethernet might just work, I don't
actually have a USB ethernet device to test with.  I'm happy with WiFi
for now.

My phone has a large 720p display, I'm really short sighted,
so when my glasses are off and the phone is at a comfortable viewing
distance, it covers about the same field of view as my desktop monitor
and at a decent resolution.  This was one of the deciding factors in
getting this particular phone.  Two other options for this phone are
the WiFi Direct to HDMI dongle I mentioned before, and the likely
possibility that Samsung will soon come out with a dongle that lets me
do USB OTG and MHL at the same time.  The MHL will get me a HDMI port I
can plug a monitor into.

As I mentioned before, squeezing storage, networking, AND video through
a single USB 2 connection means that all three will likely starve for
bandwidth.  But if that's OK with you, then USB video devices plugged
into a HUB might work.  It's not something I'll be wasting money on
just to see if it works.  USB 3 might have enough bandwidth for that,
but my phone does not have USB 3.  USB video devices are good enough
for basic 2D business type stuff, but not good for more demanding
applications.

So things are looking good.

-- 
A big old stinking pile of genius that no one wants
coz there are too many silver coated monkeys in the world.
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