<s>
The	O
HP	O
49/50	O
series	O
are	O
Hewlett-Packard	O
(	O
HP	O
)	O
manufactured	O
graphing	B-Application
calculators	I-Application
.	O
</s>
<s>
They	O
are	O
the	O
successors	O
of	O
the	O
popular	O
HP	B-Device
48	I-Device
series	I-Device
.	O
</s>
<s>
There	O
are	O
five	O
calculators	O
in	O
the	O
49/50	O
series	O
of	O
HP	O
graphing	B-Application
calculators	I-Application
.	O
</s>
<s>
These	O
calculators	O
have	O
both	O
algebraic	O
and	O
RPN	O
entry	O
modes	O
,	O
and	O
can	O
perform	O
numeric	O
and	O
symbolic	O
calculations	O
using	O
the	O
built-in	O
Computer	B-General_Concept
Algebra	I-General_Concept
System	I-General_Concept
(	O
CAS	B-General_Concept
)	O
,	O
which	O
is	O
an	O
improved	O
ALG48	O
and	O
Erable	B-Application
combination	O
from	O
the	O
HP	B-Device
48	I-Device
series	I-Device
.	O
</s>
<s>
In	O
addition	O
to	O
having	O
a	O
metallic	O
blue	O
color	O
,	O
the	O
keyboard	O
material	O
was	O
rubber	O
and	O
did	O
not	O
have	O
the	O
traditional	O
HP	B-Device
calculator	I-Device
hinged	O
keyboard	O
feel	O
.	O
</s>
<s>
In	O
addition	O
,	O
it	O
lacked	O
a	O
large	O
key	O
which	O
was	O
seen	O
by	O
many	O
as	O
the	O
defining	O
characteristic	O
of	O
an	O
HP	B-Device
calculator	I-Device
.	O
</s>
<s>
These	O
changes	O
were	O
disliked	O
by	O
many	O
traditional	O
HP	B-Device
calculator	I-Device
users	O
.	O
</s>
<s>
The	O
49G	O
incorporated	O
many	O
of	O
the	O
most	O
powerful	O
interface	O
and	O
mathematics	O
tools	O
available	O
on	O
the	O
HP	B-Device
48	I-Device
series	I-Device
into	O
the	O
firmware	B-General_Concept
of	O
the	O
new	O
49G	O
,	O
including	O
the	O
ability	O
to	O
easily	O
decompile	O
and	O
compile	O
both	O
SysRPL	O
and	O
Saturn	B-Application
assembly	B-Language
code	I-Language
on	O
the	O
unit	O
.	O
</s>
<s>
The	O
49G	O
was	O
the	O
first	O
HP	B-Device
calculator	I-Device
to	O
use	O
flash	B-Device
memory	I-Device
and	O
have	O
an	O
upgradable	O
firmware	B-General_Concept
.	O
</s>
<s>
In	O
addition	O
,	O
it	O
had	O
a	O
hard	O
sliding	O
case	O
as	O
opposed	O
to	O
the	O
soft	O
pouches	O
supplied	O
with	O
the	O
HP48	B-Device
series	O
.	O
</s>
<s>
The	O
last	O
officially	O
supported	O
firmware	B-General_Concept
update	O
for	O
the	O
49G	O
calculator	O
was	O
1.18	O
,	O
but	O
several	O
unofficial	O
firmware	B-General_Concept
versions	O
were	O
released	O
by	O
the	O
developers	O
.	O
</s>
<s>
The	O
final	O
firmware	B-General_Concept
version	O
was	O
1.19-6	O
.	O
</s>
<s>
Several	O
firmware	B-General_Concept
versions	O
for	O
the	O
successor	O
hp49g+	O
and	O
HP50g	O
calculators	O
have	O
also	O
been	O
released	O
in	O
builds	O
intended	O
for	O
PC	O
emulation	B-Application
software	I-Application
that	O
lacked	O
full	O
utilization	O
of	O
the	O
successors	O
 '	O
ARM	B-Architecture
CPU	O
.	O
</s>
<s>
Until	O
at	O
least	O
firmware	B-General_Concept
version	O
2.09	O
,	O
those	O
emulator	B-Application
builds	O
could	O
be	O
installed	O
on	O
the	O
original	O
HP49G	O
.	O
</s>
<s>
In	O
2003	O
,	O
the	O
CAS	B-General_Concept
source	O
code	O
of	O
the	O
49G	O
firmware	B-General_Concept
was	O
released	O
under	O
the	O
LGPL	B-Application
.	O
</s>
<s>
Due	O
to	O
licensing	O
restrictions	O
,	O
the	O
recompiled	O
firmware	B-General_Concept
cannot	O
be	O
redistributed	O
.	O
</s>
<s>
Instead	O
of	O
the	O
rubber	O
keyboard	O
found	O
on	O
the	O
HP49G	O
,	O
this	O
calculator	O
's	O
keyboard	O
had	O
plastic	O
hinges	O
intended	O
to	O
return	O
the	O
feel	O
of	O
older	O
HP	B-Device
calculators	I-Device
,	O
and	O
also	O
included	O
a	O
pouch	O
to	O
protect	O
the	O
unit	O
,	O
similar	O
to	O
those	O
included	O
with	O
older	O
HP	O
models	O
.	O
</s>
<s>
This	O
calculator	O
featured	O
an	O
entirely	O
new	O
processor	O
architecture	O
,	O
USB	B-Protocol
(	O
Mini-B	O
)	O
and	O
IrDA	O
(	O
IrCOMM	O
)	O
infrared	O
communication	O
,	O
memory	O
expansion	O
via	O
an	O
SD	B-Device
(	O
SDSC/MMC	O
)	O
card	O
,	O
and	O
a	O
slightly	O
larger	O
screen	O
,	O
as	O
well	O
as	O
other	O
improvements	O
over	O
the	O
previous	O
model	O
.	O
</s>
<s>
The	O
calculator	O
system	O
did	O
not	O
run	O
directly	O
on	O
the	O
new	O
ARM	B-Architecture
processor	I-Architecture
,	O
but	O
rather	O
on	O
an	O
emulation	B-Application
layer	O
for	O
the	O
older	O
Saturn	B-Application
processors	I-Application
found	O
in	O
previous	O
HP	B-Device
calculators	I-Device
.	O
</s>
<s>
This	O
allowed	O
the	O
49g+	O
to	O
maintain	O
binary-level	O
compatibility	O
with	O
most	O
of	O
the	O
programs	O
written	O
for	O
the	O
HP49G	O
calculator	O
,	O
as	O
well	O
as	O
source	O
code-level	O
compatibility	O
with	O
many	O
written	O
for	O
the	O
HP48	B-Device
series	O
.	O
</s>
<s>
Despite	O
the	O
emulation	B-Application
,	O
the	O
49g+	O
was	O
still	O
much	O
faster	O
than	O
any	O
older	O
model	O
of	O
HP	B-Device
calculator	I-Device
.	O
</s>
<s>
It	O
is	O
even	O
possible	O
to	O
run	O
programs	O
written	O
for	O
the	O
ARM	B-Architecture
processor	I-Architecture
thus	O
bypassing	O
the	O
emulation	B-Application
layer	O
completely	O
.	O
</s>
<s>
A	O
port	O
of	O
the	O
GNU	B-Application
C	I-Application
compiler	I-Application
is	O
also	O
available	O
(	O
see	O
HPGCC	O
below	O
)	O
.	O
</s>
<s>
The	O
hp	O
48gII	O
(	O
F2226A	O
)	O
,	O
which	O
was	O
announced	O
on	O
20	O
October	O
2003	O
,	O
was	O
not	O
a	O
replacement	O
for	O
the	O
HP	B-Device
48	I-Device
series	I-Device
as	O
its	O
name	O
suggested	O
.	O
</s>
<s>
Rather	O
it	O
was	O
a	O
49g+	O
,	O
also	O
with	O
an	O
ARM	B-Architecture
processor	I-Architecture
(	O
unlike	O
the	O
HP	O
48G	O
)	O
,	O
but	O
with	O
reduced	O
memory	O
,	O
no	O
expansion	O
via	O
an	O
SD	B-Device
memory	I-Device
card	I-Device
,	O
lower	O
clock	O
speed	O
,	O
a	O
smaller	O
screen	O
,	O
and	O
a	O
non-flashable	O
firmware	B-General_Concept
.	O
</s>
<s>
The	O
original	O
2003	O
version	O
had	O
128KB	O
RAM	B-Architecture
and	O
ran	O
on	O
3AAA	O
batteries	O
,	O
whereas	O
the	O
second	O
2007	O
version	O
(	O
based	O
on	O
the	O
Apple	O
V2	O
platform	O
)	O
needs	O
fourAAA	O
batteries	O
and	O
comes	O
with	O
256KB	O
RAM	B-Architecture
,	O
added	O
a	O
USB	B-Protocol
(	O
Mini-B	O
)	O
port	O
and	O
features	O
a	O
better	O
keyboard	O
.	O
</s>
<s>
The	O
most	O
apparent	O
change	O
is	O
a	O
revised	O
color	O
scheme	O
,	O
returning	O
the	O
unit	O
to	O
a	O
more	O
traditional	O
HP	B-Device
calculator	I-Device
appearance	O
.	O
</s>
<s>
The	O
form	O
and	O
size	O
of	O
the	O
calculator	O
shell	O
is	O
identical	O
to	O
the	O
49g+	O
series	O
,	O
but	O
four	O
AAA	B-Algorithm
batteries	I-Algorithm
are	O
used	O
as	O
opposed	O
to	O
three	O
in	O
previous	O
models	O
.	O
</s>
<s>
In	O
addition	O
to	O
all	O
the	O
features	O
of	O
the	O
49g+	O
,	O
the	O
50g	O
also	O
includes	O
the	O
full	O
equation	O
library	O
found	O
in	O
the	O
HP	B-Device
48G	I-Device
series	I-Device
(	O
also	O
available	O
for	O
the	O
49g+	O
with	O
firmware	B-General_Concept
2.06	O
and	O
above	O
)	O
,	O
as	O
well	O
as	O
the	O
periodic	O
table	O
library	O
originally	O
available	O
as	O
a	O
plug-in	O
card	O
for	O
the	O
48S	B-Device
series	O
,	O
as	O
of	O
firmware	B-General_Concept
2.15/	O
2.16	O
(	O
the	O
latest	O
,	O
as	O
of	O
2015	O
)	O
,	O
and	O
has	O
a	O
3.3V	O
TTL-level	O
asynchronous	O
serial	O
port	O
in	O
addition	O
to	O
IrDA	O
and	O
USB	B-Protocol
Mini-B	O
ports	O
of	O
the	O
49g+	O
.	O
</s>
<s>
A	O
worldwide	O
announcement	O
regarding	O
the	O
availability	O
of	O
this	O
calculator	O
was	O
made	O
by	O
HP	O
in	O
September	O
2006	O
,	O
and	O
official	O
details	O
were	O
available	O
on	O
the	O
HP	B-Device
calculators	I-Device
webpage	O
.	O
</s>
<s>
The	O
HP49/50	O
series	O
of	O
calculators	O
support	O
both	O
algebraic	O
and	O
a	O
stack-based	O
programming	O
language	O
named	O
RPL	B-Device
,	O
a	O
combination	O
of	O
Reverse	O
Polish	O
Notation	O
(	O
RPN	O
)	O
and	O
Lisp	B-Language
.	O
</s>
<s>
RPL	B-Device
adds	O
the	O
concepts	O
of	O
lists	O
and	O
functions	O
to	O
stack-based	O
programming	O
,	O
allowing	O
the	O
programmer	O
to	O
pass	O
unevaluated	O
code	O
as	O
arguments	O
to	O
functions	O
,	O
or	O
return	O
unevaluated	O
code	O
from	O
a	O
function	O
by	O
leaving	O
it	O
on	O
the	O
stack	B-Application
.	O
</s>
<s>
The	O
highest	O
level	O
language	O
is	O
User	O
RPL	B-Device
,	O
consisting	O
of	O
sequences	O
of	O
built-in	O
postfix	O
operations	O
,	O
optionally	O
including	O
loops	O
and	O
conditionals	O
.	O
</s>
<s>
Every	O
User	O
RPL	B-Device
command	O
checks	O
the	O
stack	B-Application
for	O
its	O
particular	O
arguments	O
and	O
returns	O
an	O
error	O
if	O
they	O
are	O
incorrect	O
or	O
not	O
present	O
.	O
</s>
<s>
Below	O
User	O
RPL	B-Device
is	O
System	O
RPL	B-Device
(	O
SysRPL	O
)	O
.	O
</s>
<s>
Most	O
System	O
RPL	B-Device
commands	O
lack	O
argument	O
checking	O
and	O
are	O
defined	O
only	O
for	O
specific	O
argument	O
types	O
(	O
e.g.	O
</s>
<s>
short	O
integer	O
vs.	O
long	O
integer	O
)	O
,	O
making	O
System	O
RPL	B-Device
programs	O
run	O
dramatically	O
faster	O
than	O
equivalent	O
User	O
RPL	B-Device
ones	O
.	O
</s>
<s>
In	O
addition	O
,	O
System	O
RPL	B-Device
includes	O
many	O
advanced	O
functions	O
that	O
are	O
not	O
available	O
in	O
User	O
RPL	B-Device
.	O
</s>
<s>
System	O
RPL	B-Device
programs	O
can	O
be	O
created	O
without	O
the	O
use	O
of	O
PC	O
software	O
(	O
although	O
it	O
is	O
available	O
)	O
,	O
thanks	O
to	O
the	O
calculator	O
's	O
built-in	O
compiler	O
,	O
MASD	O
.	O
</s>
<s>
MASD	O
also	O
can	O
compile	O
Saturn	B-Application
assembly	B-Language
language	I-Language
and	O
,	O
with	O
the	O
latest	O
firmware	B-General_Concept
revision	O
for	O
the	O
49g+	O
/50g	O
,	O
ARMv4T	O
assembly	B-Language
language	I-Language
on	O
the	O
calculator	O
itself	O
.	O
</s>
<s>
Many	O
tools	O
exist	O
to	O
assist	O
programmers	O
and	O
make	O
the	O
calculator	O
a	O
powerful	O
programming	B-Application
environment	I-Application
.	O
</s>
<s>
Saturn	B-Application
assembly	B-Language
,	O
and	O
,	O
on	O
the	O
49g+	O
/50g	O
,	O
ARM	B-Architecture
assembly	B-Language
and	O
C	B-Language
,	O
are	O
also	O
programmable	O
using	O
desktop	O
based	O
compilers	O
.	O
</s>
<s>
See	O
also	O
the	O
programs	O
available	O
for	O
the	O
HP	B-Device
48	I-Device
series	I-Device
.	O
</s>
<s>
No	O
model	O
of	O
this	O
series	O
is	O
programmable	O
in	O
HP	B-Device
PPL	I-Device
.	O
</s>
<s>
HPGCC	O
is	O
an	O
implementation	O
of	O
the	O
GCC	B-Application
compiler	I-Application
,	O
released	O
under	O
the	O
GNU	B-License
GPL	I-License
.	O
</s>
<s>
It	O
is	O
now	O
mainly	O
targeted	O
at	O
the	O
ARM-based	O
49g+	O
/50g	O
calculators	O
.	O
</s>
<s>
Previous	O
versions	O
of	O
HPGCC	O
supported	O
the	O
other	O
ARM-based	O
calculator	O
models	O
(	O
the	O
48gII	O
,	O
and	O
the	O
hp	O
39g+	O
/HP	O
39gs/HP	O
40gs	O
)	O
,	O
but	O
this	O
was	O
removed	O
due	O
to	O
lack	O
of	O
interest	O
and	O
compatibility	O
issues	O
.	O
</s>
<s>
Formally	O
,	O
HPGCC	O
is	O
a	O
cross-compiler	B-Application
;	O
it	O
compiles	O
code	O
for	O
the	O
ARM-based	O
HP	B-Device
calculators	I-Device
,	O
but	O
runs	O
on	O
a	O
PC	O
rather	O
than	O
the	O
target	O
system	O
.	O
</s>
<s>
Most	O
notably	O
,	O
the	O
compiled	O
code	O
is	O
now	O
in	O
ARM	B-Architecture
Thumb	O
mode	O
by	O
default	O
,	O
resulting	O
in	O
great	O
reduction	O
in	O
code	O
size	O
with	O
little	O
performance	O
hit	O
.	O
</s>
<s>
Besides	O
implementing	O
most	O
of	O
ANSIC	O
,	O
there	O
are	O
device-specific	O
libraries	O
that	O
allow	O
access	O
to	O
things	O
like	O
the	O
calculator	O
's	O
RPN	O
stack	B-Application
,	O
memory	O
and	O
piezoelectric	O
buzzer	O
.	O
</s>
<s>
The	O
GCC	B-Application
compiler	I-Application
itself	O
is	O
the	O
property	O
of	O
the	O
Free	O
Software	O
Foundation	O
,	O
and	O
they	O
state	O
that	O
its	O
use	O
does	O
not	O
impose	O
any	O
particular	O
licensing	O
restrictions	O
on	O
any	O
of	O
its	O
output	O
.	O
</s>
<s>
However	O
,	O
the	O
libraries	O
included	O
with	O
HPGCC	O
,	O
including	O
routines	O
necessary	O
to	O
actually	O
invoke	O
any	O
HPGCC-compiled	O
program	O
on	O
an	O
actual	O
calculator	O
,	O
are	O
released	O
under	O
a	O
modified	O
GPL	B-License
license	I-License
,	O
contrary	O
to	O
GCC	B-Application
on	O
many	O
other	O
platforms	O
which	O
use	O
a	O
more	O
permissive	B-License
license	I-License
for	O
their	O
libraries	O
.	O
</s>
<s>
Thus	O
any	O
programs	O
that	O
link	O
against	O
them	O
can	O
only	O
be	O
distributed	O
if	O
they	O
are	O
also	O
released	O
under	O
the	O
GPL	B-License
(	O
with	O
an	O
exception	O
for	O
"	O
non-profit	O
"	O
software	O
)	O
.	O
</s>
<s>
Linux	B-Application
,	O
Windows	O
,	O
and	O
MacOSX	O
versions	O
are	O
available	O
for	O
download	O
.	O
</s>
<s>
The	O
Windows	O
version	O
also	O
includes	O
a	O
version	O
of	O
Programmer	O
's	O
Notepad	O
for	O
a	O
basic	O
IDE	B-Application
.	O
</s>
<s>
There	O
are	O
several	O
emulators	B-Application
available	O
for	O
the	O
HP	O
49G	O
calculator	O
.	O
</s>
<s>
A	O
version	O
of	O
EMU48	O
is	O
available	O
in	O
the	O
Debug4x	O
IDE	B-Application
that	O
allows	O
emulation	B-Application
of	O
most	O
of	O
the	O
features	O
of	O
the	O
49g+	O
/50g	O
,	O
but	O
will	O
not	O
execute	O
any	O
ARM-based	O
code	O
.	O
</s>
<s>
An	O
ARM-based	O
emulator	B-Application
,	O
x49gp	O
,	O
has	O
been	O
released	O
and	O
allows	O
the	O
true	O
emulation	B-Application
of	O
the	O
49g+	O
/50g	O
ARM	B-Architecture
processor	I-Architecture
and	O
successfully	O
runs	O
HPGCC	O
2	O
and	O
3	O
compiled	O
programs	O
.	O
</s>
<s>
The	O
emulator	B-Application
is	O
only	O
available	O
for	O
Linux	B-Application
and	O
Mac	O
OS	O
X	O
and	O
must	O
be	O
compiled	O
from	O
the	O
source	O
.	O
</s>
<s>
So	O
far	O
,	O
there	O
are	O
no	O
49g+	O
/50g	O
emulators	B-Application
for	O
smartphones	O
with	O
the	O
exception	O
of	O
HP	O
50g	O
for	O
iPhone	O
and	O
iPad	O
released	O
in	O
October	O
2012	O
.	O
</s>
<s>
An	O
emulator	B-Application
for	O
Microsoft	B-Operating_System
Windows	I-Operating_System
Mobile	I-Operating_System
(	O
PPC	O
,	O
smartphones	O
)	O
is	O
available	O
.	O
</s>
<s>
Other	O
49G/49g	O
+	O
/50g	O
emulators	B-Application
for	O
Android	O
(	O
without	O
ARM	B-Architecture
support	O
)	O
.	O
</s>
<s>
In	O
2012	O
,	O
Hewlett-Packard	O
released	O
an	O
emulator	B-Application
named	O
HP	O
50g	O
Virtual	O
Calculator	O
(	O
version	O
3.1.29/3.1.30	O
with	O
firmware	B-General_Concept
2.16	O
and	O
support	O
for	O
the	O
StreamSmart	O
410	O
)	O
for	O
Windows	O
.	O
</s>
<s>
The	O
49/50	O
series	O
allows	O
the	O
user	O
to	O
update	O
the	O
firmware	B-General_Concept
to	O
gain	O
enhanced	O
features	O
or	O
bug	O
fixes	O
.	O
</s>
<s>
Official	O
firmware	B-General_Concept
updates	O
are	O
released	O
by	O
Hewlett-Packard	O
.	O
</s>
<s>
Unsupported	O
unofficial	O
firmware	B-General_Concept
updates	O
are	O
also	O
available	O
at	O
sites	O
such	O
as	O
hpcalc.org	O
.	O
</s>
