[Noisebridge-discuss] Android/arduino questions

[Jonathan Lassoff]

On Wed, Jun 8, 2011 at 4:15 PM, rachel lyra hospodar
<rachel at mediumreality.com> wrote:
> thanks for the answers!  your reward is... more questions!
>
> my understanding of the ADK package so far is this:
>
> a fancy arduino that comes with a bunch of sensor bells and whistles all
> attached, as well as additional chips (such as an FTDI) that give it
> more flexibility.
> also adk is a software tool that runs on the phone to receive and
> interpret the signals.
>
> correct so far?

That's what I know it so far.

> it looks like the arduino in the kit is designed to only connect to the
> phone with a usb cable, i have been assuming that it would be possible
> to somehow replace that cable with wireless radios.  i have done some
> work using xbee and hope rf, and haven't dabbled in bluetooth yet BUT
> just found out about a way to get into it without spending an arm and a
> leg so i plan to start trying it out.  i am guessing there might be some
> differences to using the adk arduino and a bluetooth to talk bluetooth
> to the phone itself, vs attaching an external (maybe xbee) radio to the
> phone's usb port and another one to to the arduino... because if i am
> attaching an external radio i would think it would be possible to make
> the xbee's signals look, to the phone, indistinguishable from if i had
> simply used wires instead.  maybe i would need to attach a second
> arduino on the phone end to decode signals from the radio?  maybe not?
> i think that question is more about the functionality of those radios, i
> will have to refresh myself on their capabilities.

Well, I think you can probably pretty easily hook up a wireless
component by adding a bluetooth like this
(http://www.sparkfun.com/products/10393) and pinning it out to work
with the Arduino Mega pinout. However, getting that to work with the
accessory API and interface inside of the Android project will
probably be a lot more Java work.

If you're just trying to get some data into a single app, it's
probably easier to just use a phone's built-in bluetooth radio for the
Serial Port Profile (SPP). I have no idea how easy or hard that would
be to hook into a Java app on the phone, but I'd guess it's doable.

> so assuming that i am running the adk software on the phone, without a
> specific need for the bell or whistle in question, is there any real
> reason to use the arduino they packaged in the adk?  or any physical
> part of the kit at all?  what does a generic arduino need in order to
> plug into the usb port on the phone?  firmware? usb chip? something else
> that i am missing?

I think you just need something that will act as a USB device, nothing
special. It just needs to emulate the right device class and talk the
right API if you want to hook into the accessory APIs on the phone.

> is it possible to use the standards that adk establishes with the
> bluetooth functionality that amarino enables?

I think these are two separate things. As far as I know, it's not
possible to speak the accessory API over anything over than USB at the
moment. I'm sure that could change in the future to run over Bluetooth
SPP or something.