<s>
The	O
AVR	B-Device
Butterfly	I-Device
is	O
a	O
battery-powered	O
single-board	B-Device
microcontroller	I-Device
developed	O
by	O
Atmel	O
.	O
</s>
<s>
It	O
consists	O
of	O
an	O
Atmel	O
ATmega169PV	B-Architecture
Microcontroller	B-Architecture
,	O
a	O
liquid	B-Device
crystal	I-Device
display	I-Device
,	O
joystick	B-Device
,	O
speaker	O
,	O
serial	B-Protocol
port	I-Protocol
,	O
real-time	O
clock	O
(	O
RTC	O
)	O
,	O
internal	O
flash	B-Device
memory	I-Device
,	O
and	O
sensors	O
for	O
temperature	O
and	O
voltage	O
.	O
</s>
<s>
The	O
board	O
is	O
the	O
size	O
of	O
a	O
name	O
tag	O
and	O
has	O
a	O
clothing	O
pin	O
on	O
back	O
so	O
it	O
can	O
be	O
worn	O
as	O
such	O
after	O
the	O
user	O
enters	O
their	O
name	O
onto	O
the	O
LCD	B-Device
.	O
</s>
<s>
The	O
AVRButterfly	O
demonstrates	O
LCD	B-Device
driving	O
by	O
running	O
a	O
14	B-General_Concept
segment	I-General_Concept
,	O
six	O
alpha-numeric	O
character	O
display	O
.	O
</s>
<s>
However	O
,	O
the	O
LCD	B-Device
interface	O
consumes	O
many	O
of	O
the	O
I/O	B-General_Concept
pins	O
.	O
</s>
<s>
The	O
Butterfly	O
's	O
ATmega169	B-Architecture
CPU	O
is	O
capable	O
of	O
speeds	O
up	O
to	O
8MHz	O
,	O
however	O
it	O
is	O
factory	O
set	O
by	O
software	O
to	O
2MHz	O
to	O
preserve	O
the	O
button	O
battery	O
life	O
.	O
</s>
<s>
There	O
are	O
free	O
replacement	O
bootloaders	B-Application
available	O
that	O
will	O
launch	O
programs	O
at	O
1	O
,	O
2	O
,	O
4	O
or	O
8MHz	O
speeds	O
.	O
</s>
<s>
The	O
Butterfly	O
comes	O
preloaded	O
with	O
software	O
that	O
demonstrates	O
many	O
features	O
of	O
the	O
ATmega169	B-Architecture
,	O
including	O
reading	O
of	O
the	O
ambient	O
light	O
level	O
and	O
temperature	O
and	O
playback	O
of	O
musical	O
notes	O
.	O
</s>
<s>
The	O
device	O
has	O
a	O
clothing-pin	O
attached	O
to	O
the	O
back	O
,	O
so	O
it	O
may	O
be	O
worn	O
as	O
a	O
name	O
tag	O
—	O
the	O
"	O
name	O
"	O
may	O
be	O
entered	O
via	O
the	O
joystick	B-Device
or	O
over	O
the	O
RS-232	O
port	O
,	O
and	O
will	O
scroll	O
across	O
the	O
LCD	B-Device
.	O
</s>
<s>
The	O
Butterfly	O
can	O
be	O
freely	O
reprogrammed	O
using	O
the	O
same	O
toolchains	O
as	O
for	O
many	O
other	O
AVR	B-Architecture
controllers	I-Architecture
,	O
for	O
example	O
using	O
the	O
Atmel	B-Architecture
AVR	I-Architecture
assembly	O
language	O
or	O
the	O
free	O
integrated	B-Application
development	I-Application
environment	I-Application
(	O
IDE	O
)	O
Atmel	O
Studio	O
for	O
programming	O
in	O
C	B-Language
.	O
</s>
<s>
A	O
pre-installed	O
bootloader	B-Application
allows	O
the	O
board	O
to	O
be	O
re-programmed	O
with	O
a	O
standard	O
RS-232	O
serial	B-Protocol
port	I-Protocol
,	O
requiring	O
no	O
special	O
hardware	O
.	O
</s>
<s>
The	O
board	O
also	O
has	O
ISP	B-Device
and	O
JTAG	O
ports	O
for	O
in-circuit	B-Device
programming	I-Device
and	O
debugging	O
.	O
</s>
<s>
Project	O
ButtLoad	O
offers	O
free	O
plans	O
to	O
convert	O
the	O
Butterfly	O
into	O
a	O
portable	O
AVR-ISP	O
for	O
programming	O
other	O
AVR	O
devices	O
.	O
</s>
<s>
C	B-Language
Programming	I-Language
for	O
Microcontrollers	B-Architecture
,	O
a	O
book	O
for	O
learning	O
to	O
program	O
AVRs	O
using	O
C	B-Language
,	O
was	O
written	O
for	O
the	O
Butterfly	O
as	O
development	O
platform	O
.	O
</s>
<s>
The	O
Butterfly	O
Logger	O
is	O
an	O
open	O
source	O
data	O
logger	O
based	O
on	O
the	O
AVR	B-Device
Butterfly	I-Device
.	O
</s>
<s>
The	O
Butteruino	O
project	O
is	O
a	O
set	O
of	O
libraries	O
to	O
integrate	O
the	O
AVR	B-Device
Butterfly	I-Device
with	O
the	O
Arduino	O
development	O
environment	O
.	O
</s>
