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Sunday, October 23, 2011

IOIO First Impressions

I picked up a IOIO (apparently pronounced YoYo) from Android Open and I have just had chance to play with it.

Unlike the Arduino, IOIO is not intended to operate independently. It has to be paired with an Android phone. While it can use the Android Open Accessory protocol, it can also use plain old ADB which means that it works on most phones rather than the smaller choice of phones that Open Accessory works on.

I even tried an old Android 1.6 LG phone that one of my kids cast off six months ago and it works just fine.

When creating a project, you do not change the firmware on the IOIO, but rather you issue commands that read values from pins and turn pins on and off from the Android app.

It took 10 minutes to get the example working that turns the on-board LED on and off from a little Android app. Although I had Eclipse and the Android SDK already installed. These are probably the most complex part of setting up.

IOIO sets out to do just one job and do it well. It is not a general purpose board like the Arduino, and for $50, it is just cheaper than an Arduino and USB host shield and smaller and neater.

I like it a lot and it looks great. Far more IO ports than you are ever likely to use. In fact, I will probably solder 0.2 inch screw terminals onto the connectors and just use make every other IO available.

Pros.
Pot to adjust charging current to phone
Nice looking board
Good documentation set on the Wiki (https://github.com/ytai/ioio/wiki)

Cons.
Only 20mA output current per IO pin (Arduino can do 40mA)
3.3V logic, but some pulls can cope with being pulled up to 5V
No Power socket, you have to solder power leads on. This means that to do anything with the board, you will need to solder.

Edit: I forgot to mention that IOIOs with the latest firmware can accept a cheap Bluetooth dongle and work seamlessly over BT. Even switching connection without restart if you plug in with USB.


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4 comments:

jswanson said...

...quickly filling up pins
http://swantron.com/pushing-to-master/
...love the IOIO. Good luck!

Ytai said...

Thanks for the great write up!
Just updating (add to pros :D ) - there's now Bluetooth dongle support.

Simon Monk said...

Hi, yes, i saw that at Open Android. I think we talked briefly. Great bit of work.

That can be part 2 of the writeup if I can find my USB dongle. Also, I haven't checked my IOIO to see if I have the new firmware.

Simon Monk said...

My book 'Making Android Accessories with IOIO' is out now. You will find it on Amazon etc.