<s>
IOIO	B-Application
(	O
pronounced	O
yo-yo	O
)	O
is	O
a	O
series	O
of	O
open	B-License
source	I-License
PIC	O
microcontroller-based	O
boards	O
that	O
allow	O
Android	B-Application
mobile	I-Application
applications	O
to	O
interact	O
with	O
external	O
electronics	O
.	O
</s>
<s>
The	O
name	O
"	O
IOIO	B-Application
"	O
is	O
inspired	O
by	O
the	O
function	O
of	O
the	O
device	O
,	O
which	O
enables	O
applications	O
to	O
receive	O
external	O
input	O
(	O
"	O
I	O
"	O
)	O
and	O
produce	O
external	O
output	O
(	O
"	O
O	O
"	O
)	O
.	O
</s>
<s>
The	O
IOIO	B-Application
board	O
contains	O
a	O
single	O
PIC	B-Architecture
MCU	I-Architecture
that	O
acts	O
as	O
a	O
USB	B-Protocol
host/USB	O
slave	O
and	O
communicates	O
with	O
an	O
Android	B-Application
app	I-Application
running	O
on	O
a	O
connected	O
Android	B-Application
device	O
.	O
</s>
<s>
The	O
board	O
provides	O
connectivity	O
via	O
USB	B-Protocol
,	O
USB-OTG	O
or	O
Bluetooth	B-Protocol
,	O
and	O
is	O
controllable	O
from	O
within	O
an	O
Android	B-Application
application	I-Application
using	O
the	O
Java	B-Language
API	O
.	O
</s>
<s>
In	O
addition	O
to	O
basic	O
digital	B-Architecture
input/output	I-Architecture
and	O
analog	O
input	O
,	O
the	O
IOIO	B-Application
library	O
also	O
handles	O
PWM	B-Algorithm
,	O
I2C	O
,	O
SPI	B-Architecture
,	O
UART	O
,	O
Input	B-Device
capture	I-Device
,	O
Capacitive	B-Device
sensing	I-Device
and	O
advanced	O
motor	O
control	O
.	O
</s>
<s>
To	O
connect	O
to	O
older	O
Android	B-Application
devices	O
that	O
use	O
USB	B-Protocol
2.0	O
in	O
slave	O
mode	O
,	O
newer	O
IOIO	B-Application
models	O
use	O
USB	B-Protocol
On-The-Go	O
to	O
act	O
as	O
a	O
host	O
for	O
such	O
devices	O
.	O
</s>
<s>
Some	O
models	O
also	O
support	O
the	B-Application
Google	I-Application
Open	O
Accessory	O
USB	B-Protocol
protocol	O
.	O
</s>
<s>
The	O
IOIO	B-Application
motor	O
control	O
API	O
can	O
drive	O
up	O
to	O
9	O
motors	O
and	O
any	O
number	O
of	O
binary	O
actuators	O
in	O
synchronization	O
and	O
cycle-accurate	O
precision	O
.	O
</s>
<s>
Developers	O
may	O
send	O
a	O
sequence	O
of	O
high-level	O
commands	O
to	O
the	O
IOIO	B-Application
,	O
which	O
performs	O
the	O
low-level	O
waveform	O
generation	O
on-chip	O
.	O
</s>
<s>
The	O
IOIO	B-Application
firmware	O
supports	O
3	O
different	O
kinds	O
of	O
motors	O
;	O
stepper	B-Algorithm
motors	I-Algorithm
,	O
DC	O
motors	O
and	O
servo	B-Algorithm
motors	I-Algorithm
.	O
</s>
<s>
For	O
first-generation	O
devices	O
updating	O
is	O
performed	O
using	O
an	O
Android	B-Application
device	O
and	O
the	O
IOIO	B-Application
Manager	O
application	O
available	O
on	O
Google	B-Application
Play	I-Application
.	O
</s>
<s>
Second-generation	O
IOIO-OTG	O
devices	O
must	O
be	O
updated	O
using	O
a	O
desktop	O
computer	O
running	O
the	O
IOIODude	O
application	O
.	O
</s>
<s>
The	O
IOIO	B-Application
supports	O
both	O
computers	O
and	O
Android	B-Application
devices	O
as	O
first-class	O
hosts	O
,	O
and	O
provides	O
the	O
exact	O
API	O
on	O
both	O
types	O
of	O
devices	O
.	O
</s>
<s>
First-generation	O
devices	O
can	O
only	O
communicate	O
with	O
PCs	O
over	O
Bluetooth	B-Protocol
,	O
while	O
IOIO-OTG	O
devices	O
can	O
use	O
either	O
Bluetooth	B-Protocol
or	O
USB	B-Protocol
.	O
</s>
<s>
PC	O
applications	O
may	O
use	O
APIs	O
for	O
Java	B-Language
or	O
C#	B-Application
to	O
communicate	O
with	O
the	O
board	O
;	O
Java	B-Language
being	O
the	O
official	O
API	O
.	O
</s>
<s>
The	O
IOIO	B-Application
hardware	O
and	O
software	O
is	O
entirely	O
open	B-License
source	I-License
,	O
and	O
enabled	O
the	O
creation	O
of	O
hundreds	O
of	O
DIY	O
robotic	O
projects	O
around	O
the	O
world	O
.	O
</s>
<s>
The	O
board	O
has	O
been	O
featured	O
in	O
various	O
learning	O
kits	O
,	O
which	O
aim	O
to	O
help	O
students	O
write	O
Android	B-Application
applications	I-Application
that	O
can	O
interact	O
with	O
the	O
external	O
world	O
.	O
</s>
<s>
The	O
Qualcomm	B-Architecture
Snapdragon	I-Architecture
Micro	O
Rover	O
is	O
a	O
3D	O
printed	O
robot	O
that	O
leverages	O
an	O
Android	B-Application
smartphone	B-Application
and	O
the	O
IOIO	B-Application
to	O
control	O
the	O
robot	O
's	O
motors	O
and	O
sensors	O
.	O
</s>
<s>
Guy	O
Hoffman	O
created	O
an	O
emotionally-sensitive	O
robot	O
,	O
that	O
relies	O
on	O
the	O
IOIO	B-Application
to	O
control	O
the	O
robot	O
's	O
hardware	O
.	O
</s>
<s>
The	O
IOIO	B-Application
has	O
been	O
variously	O
described	O
as	O
a	O
"	O
geek	O
's	O
paradise	O
"	O
,	O
"	O
an	O
easy	O
way	O
to	O
get	O
I/O	O
from	O
an	O
Android	B-Application
device	O
’s	O
USB	B-Protocol
connection	O
"	O
and	O
"	O
a	O
USB	B-Protocol
I/O	O
breakout	O
board	O
for	O
Android	B-Application
smartphones	B-Application
which	O
turns	O
your	O
handset	O
into	O
a	O
super-Arduino	O
of	O
sorts	O
"	O
.	O
</s>
<s>
The	O
first-generation	O
IOIO	B-Application
boards	O
(	O
known	O
as	O
IOIO	B-Application
V1	O
)	O
contain	O
the	O
following	O
on-board	O
features	O
:	O
This	O
generation	O
only	O
supports	O
USB	B-Protocol
slave	O
mode	O
,	O
and	O
requires	O
a	O
USB	B-Protocol
master	O
as	O
the	O
host	O
(	O
PC	O
or	O
newer	O
Android	B-Application
phones	I-Application
)	O
.	O
</s>
<s>
The	O
IOIO	B-Application
V1	O
is	O
a	O
3.3V	O
logic	O
level	O
device	O
,	O
and	O
features	O
a	O
5V	O
DC/DC	O
switching	O
regulator	O
and	O
a	O
3.3V	O
linear	O
regulator	O
.	O
</s>
<s>
This	O
facilitates	O
charging	O
a	O
connected	O
Android	B-Application
device	O
as	O
well	O
as	O
driving	O
several	O
small	O
motors	O
or	O
similar	O
loads	O
.	O
</s>
<s>
Feature	O
Details	O
Description	O
USB	B-Protocol
connector	O
type	O
A	O
,	O
female	O
Used	O
to	O
connect	O
to	O
the	O
Android	B-Application
device	O
.	O
</s>
<s>
Some	O
have	O
special	O
functions	O
,	O
such	O
as	O
ADC	O
,	O
Input	B-Device
Capture	I-Device
,	O
UART	O
,	O
PWM	B-Algorithm
,	O
Comparator	O
or	O
for	O
programming	O
the	O
PIC	B-Architecture
MCU	I-Architecture
(	O
ICSP	B-Device
)	O
.	O
</s>
<s>
Power	O
LED	O
Lights	O
when	O
the	O
IOIO	B-Application
is	O
getting	O
power	O
.	O
</s>
<s>
Its	O
purpose	O
is	O
for	O
programming	O
new	O
bootloader	O
firmware	O
on	O
the	O
IOIO	B-Application
board	O
.	O
</s>
<s>
Charge	O
current	O
trimmer	O
(	O
CHG	O
)	O
Adjusts	O
the	O
amount	O
of	O
charge	O
current	O
supplied	O
on	O
the	O
VBUS	O
line	O
of	O
the	O
USB	B-Protocol
to	O
the	O
Android	B-Application
device	O
.	O
</s>
<s>
The	O
second-generation	O
IOIO	B-Application
boards	O
(	O
known	O
as	O
IOIO-OTG	O
)	O
contain	O
the	O
following	O
on-board	O
features	O
:	O
As	O
the	O
name	O
suggests	O
,	O
a	O
key	O
feature	O
of	O
this	O
generation	O
is	O
the	O
introduction	O
of	O
USB-OTG	O
,	O
supporting	O
USB	B-Protocol
master	O
or	O
slave	O
mode	O
.	O
</s>
<s>
This	O
enables	O
the	O
IOIO	B-Application
to	O
connect	O
to	O
older	O
Android	B-Application
phones	I-Application
that	O
only	O
support	O
USB	B-Protocol
slave	O
mode	O
,	O
in	O
addition	O
.	O
</s>
<s>
The	O
IOIO-OTG	O
is	O
a	O
3.3V	O
logic	O
level	O
device	O
,	O
with	O
some	O
of	O
the	O
pins	O
being	O
5V	O
tolerant	O
.	O
</s>
<s>
This	O
facilitates	O
charging	O
a	O
connected	O
Android	B-Application
device	O
as	O
well	O
as	O
driving	O
several	O
small	O
motors	O
or	O
similar	O
loads	O
.	O
</s>
<s>
Feature	O
Details	O
Description	O
USB	B-Protocol
connector	O
micro-AB	O
,	O
female	O
Used	O
to	O
connect	O
to	O
host	O
computer	O
,	O
an	O
Android	B-Application
device	O
or	O
a	O
Bluetooth	B-Protocol
dongle	O
.	O
</s>
<s>
Some	O
have	O
special	O
functions	O
,	O
such	O
as	O
ADC	O
,	O
Input	B-Device
Capture	I-Device
,	O
UART	O
,	O
PWM	B-Algorithm
,	O
Comparator	O
or	O
for	O
programming	O
the	O
PIC	B-Architecture
MCU	I-Architecture
(	O
ICSP	B-Device
)	O
.	O
</s>
<s>
PWR	O
LED	O
red	O
Lights	O
when	O
the	O
IOIO	B-Application
is	O
getting	O
power	O
.	O
</s>
<s>
Its	O
purpose	O
is	O
for	O
programming	O
new	O
bootloader	O
firmware	O
on	O
the	O
IOIO	B-Application
board	O
.	O
</s>
<s>
BOOT	O
pin	O
Special	O
pin	O
used	O
for	O
getting	O
the	O
IOIO	B-Application
into	O
bootloader	O
mode	O
on	O
power-up	O
.	O
</s>
<s>
Charge	O
current	O
trimmer	O
(	O
CHG	O
)	O
Adjusts	O
the	O
amount	O
of	O
current	O
supplied	O
on	O
the	O
VBUS	O
line	O
of	O
the	O
USB	B-Protocol
when	O
acting	O
as	O
a	O
USB	B-Protocol
host	O
.	O
</s>
<s>
Typically	O
used	O
in	O
battery-powered	O
application	O
with	O
Android	B-Application
to	O
prevent	O
the	O
Android	B-Application
from	O
draining	O
the	O
battery	O
quickly	O
.	O
</s>
<s>
Host	O
switch	O
In	O
"	O
A	O
"	O
mode	O
,	O
the	O
IOIO-OTG	O
will	O
detect	O
whether	O
it	O
should	O
act	O
as	O
host	O
or	O
as	O
device	O
automatically	O
,	O
according	O
to	O
whichever	O
USB	B-Protocol
connector	O
is	O
plugged	O
in	O
(	O
micro-A	O
or	O
micro-B	O
)	O
.	O
</s>
<s>
To	O
support	O
non-standard	O
USB	B-Protocol
cables	O
or	O
adapters	O
that	O
use	O
micro-B	O
type	O
,	O
move	O
the	O
switch	O
to	O
the	O
"	O
H	O
"	O
position	O
to	O
force	O
host	O
mode	O
.	O
</s>
