<s>
The	O
HP-19C	B-Device
and	O
HP-29C	B-Device
were	O
scientific/engineering	O
pocket	O
calculators	O
made	O
by	O
Hewlett-Packard	O
between	O
1977	O
and	O
1979	O
.	O
</s>
<s>
They	O
were	O
the	O
most	O
advanced	O
and	O
last	O
models	O
of	O
the	O
"	O
20	O
"	O
family	O
(	O
compare	O
HP-25	B-Device
)	O
and	O
included	O
Continuous	B-Device
Memory	I-Device
(	O
battery-backed	O
CMOS	B-Device
memory	I-Device
)	O
as	O
a	O
standard	O
feature	O
.	O
</s>
<s>
The	O
HP-19C	B-Device
included	O
a	O
small	O
thermal	O
printer	O
,	O
one	O
of	O
the	O
very	O
few	O
hand-held	O
scientific	O
calculators	O
to	O
offer	O
such	O
a	O
feature	O
(	O
HP-91	O
,	O
HP-92	O
and	O
HP-97	B-Device
were	O
desktop	O
units	O
and	O
later	O
models	O
like	O
the	O
HP-41C	B-Device
only	O
supported	O
external	O
printers	O
)	O
.	O
</s>
<s>
Due	O
to	O
the	O
printer	O
's	O
power	O
requirements	O
,	O
the	O
19C	O
used	O
a	O
battery	O
pack	O
of	O
four	O
AA-sized	O
NiCd	O
cells	O
,	O
adding	O
to	O
the	O
weight	O
of	O
the	O
calculator	O
and	O
printer	O
mechanism	O
.	O
</s>
<s>
Users	O
could	O
develop	O
software	O
for	O
the	O
HP-29C/19C	O
,	O
such	O
as	O
a	O
prime	O
number	O
generator	O
.	O
</s>
<s>
The	O
calculators	O
expanded	O
the	O
HP-25	B-Device
'	O
s	O
program	O
capabilities	O
by	O
adding	O
subroutines	O
,	O
increment/decrement	O
looping	O
,	O
relative	O
branching	O
and	O
indirect	O
addressing	O
(	O
via	O
register	O
0	O
as	O
index	O
)	O
.	O
</s>
<s>
The	O
HP-19C	B-Device
and	O
HP-29C	B-Device
were	O
introduced	O
at	O
MSRPs	O
of	O
$345	O
and	O
$195	O
,	O
respectively	O
.	O
</s>
