<s>
Elektronika	B-Device
B3-34	I-Device
(	O
Cyrillic	O
:	O
Электроника	O
Б3-34	O
)	O
was	O
a	O
Soviet	O
programmable	B-Application
calculator	I-Application
.	O
</s>
<s>
B3-34	B-Device
used	O
reverse	O
Polish	O
notation	O
and	O
had	O
98	O
bytes	O
of	O
instruction	O
memory	O
,	O
four	O
stack	O
user	O
registers	O
and	O
14	O
addressable	O
registers	O
.	O
</s>
<s>
Each	O
register	O
could	O
store	O
up	O
to	O
8	O
mantissa	B-Algorithm
or	O
Significand	B-Algorithm
digits	O
and	O
two	O
exponent	O
digits	O
in	O
the	O
range	O
to	O
.	O
</s>
<s>
The	O
first	O
programmable	O
battery-powered	O
pocket	O
calculator	O
Elektronika	B-Device
B3-21	I-Device
was	O
developed	O
by	O
the	O
end	O
of	O
1977	O
and	O
released	O
at	O
the	O
beginning	O
of	O
1978	O
.	O
</s>
<s>
Its	O
successor	O
,	O
B3-34	B-Device
,	O
was	O
n't	O
backward	O
compatible	O
with	O
B3-21	B-Device
.	O
</s>
<s>
The	O
instruction	O
set	O
,	O
hardware	O
architecture	O
and	O
microcode	B-Device
of	O
the	O
B3-34	B-Device
defined	O
the	O
standard	O
of	O
the	O
later	O
Soviet	O
programmable	O
hand-held	O
and	O
office-desk	O
calculators	O
:	O
,	O
,	O
,	O
.	O
</s>
<s>
Model	O
numbers	O
do	O
not	O
follow	O
any	O
special	O
order	O
:	O
MK-54	O
is	O
a	O
slightly	O
upgraded	O
version	O
of	O
B3-34	B-Device
and	O
MK-56	O
is	O
its	O
desktop	O
copy	O
,	O
while	O
MK-61	O
and	O
MK-52	O
are	O
somewhat	O
more	O
advanced	O
calculators	O
with	O
more	O
operations	O
and	O
even	O
EEPROM	B-General_Concept
(	O
MK-52	O
only	O
)	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
calculator	O
or	O
hand-held	O
computer	O
MK-90	O
,	O
which	O
had	O
a	O
graphic	O
LCD	O
display	O
and	O
an	O
internal	O
BASIC	O
interpreter	O
,	O
was	O
essentially	O
a	O
pocket-sized	O
variety	O
of	O
the	O
PDP-11	B-Device
.	O
</s>
<s>
Due	O
to	O
their	O
high	O
price	O
and	O
the	O
growing	O
popularity	O
of	O
much	O
more	O
powerful	O
personal	B-Device
computers	I-Device
,	O
such	O
as	O
ZX	B-Operating_System
Spectrum	I-Operating_System
,	O
these	O
powerful	O
calculators	O
never	O
gained	O
popularity	O
among	O
the	O
general	O
Soviet	O
population	O
.	O
</s>
<s>
Therefore	O
,	O
the	O
B3-34-derived	O
calculators	O
are	O
remembered	O
by	O
many	O
as	O
their	O
"	O
first	O
computer	O
"	O
.	O
</s>
<s>
Despite	O
very	O
limited	O
capability	O
,	O
people	O
managed	O
to	O
write	O
all	O
kinds	O
of	O
programs	O
for	O
B3-34	B-Device
and	O
its	O
later	O
successors	O
,	O
including	O
adventure	O
games	O
and	O
libraries	O
of	O
sophisticated	O
calculus-related	O
functions	O
for	O
engineers	O
.	O
</s>
<s>
During	O
1985	O
–	O
1986	O
the	O
science	O
magazine	O
Tekhnika	O
Molodezhi	O
published	O
a	O
science	O
fiction	O
story	O
"	O
Way	O
to	O
Earth	O
"	O
accompanied	O
by	O
programs	O
for	O
B3-34	B-Device
that	O
could	O
be	O
used	O
to	O
simulate	O
a	O
particular	O
segment	O
of	O
Moon-Earth	O
journey	O
from	O
the	O
story	O
.	O
</s>
<s>
The	O
Elektronika	O
MK-52	O
calculator	O
(	O
using	O
the	O
extended	O
B3-34	B-Device
command	O
set	O
,	O
and	O
featuring	O
internal	O
EEPROM	B-General_Concept
memory	O
for	O
storing	O
programs	O
and	O
external	O
interface	O
for	O
EEPROM	B-General_Concept
cards	O
and	O
other	O
periphery	O
)	O
was	O
used	O
in	O
the	O
Soviet	O
spacecraft	O
program	O
(	O
for	O
Soyuz	O
TM-7	O
flight	O
)	O
as	O
a	O
backup	O
for	O
the	O
on-board	O
computer	O
.	O
</s>
<s>
This	O
series	O
of	O
calculators	O
was	O
also	O
noted	O
for	O
a	O
large	O
number	O
of	O
highly	O
counter-intuitive	O
mysterious	O
undocumented	O
features	O
,	O
not	O
unlike	O
the	O
"	O
synthetic	B-Device
programming	I-Device
"	O
of	O
the	O
American	O
HP-41	B-Device
,	O
which	O
were	O
exploited	O
by	O
applying	O
normal	O
arithmetic	O
operations	O
to	O
error	O
messages	O
,	O
jumping	O
to	O
non-existent	O
addresses	O
and	O
other	O
techniques	O
.	O
</s>
<s>
A	O
number	O
of	O
respected	O
monthly	O
publications	O
,	O
including	O
the	O
popular	O
science	O
magazine	O
"	O
Nauka	O
i	O
Zhizn	O
"	O
(	O
"	O
Science	O
and	O
Life	O
"	O
)	O
,	O
featured	O
special	O
columns	O
,	O
dedicated	O
to	O
optimization	O
techniques	O
for	O
calculator	O
programmers	O
and	O
updates	O
on	O
undocumented	O
features	O
for	O
hackers	O
,	O
which	O
grew	O
into	O
a	O
whole	O
esoteric	O
science	O
with	O
many	O
branches	O
,	O
known	O
as	O
"	O
errorology	O
"	O
(	O
Russian	O
"	O
еггогология	B-Device
,	O
"	O
transliterated	O
"	O
yeggogologiya	O
"	O
)	O
.	O
</s>
<s>
B3-34	B-Device
and	O
its	O
derivatives	O
helped	O
many	O
Soviet	O
programmers	O
to	O
develop	O
their	O
skills	O
,	O
because	O
programming	O
and	O
debugging	O
required	O
ability	O
to	O
read	O
and	O
write	O
machine	O
code	O
and	O
optimize	O
literally	O
every	O
byte	O
of	O
the	O
program	O
.	O
</s>
<s>
The	O
microcode	B-Device
of	O
those	O
calculators	O
remains	O
only	O
partially	O
published	O
and	O
some	O
of	O
their	O
"	O
dark	O
secrets	O
"	O
are	O
still	O
a	O
mystery	O
and	O
are	O
still	O
being	O
researched	O
by	O
some	O
enthusiasts	O
.	O
</s>
<s>
Like	O
the	O
HP-41	B-Device
series	O
in	O
the	O
Western	O
countries	O
,	O
the	O
B3-34	B-Device
and	O
its	O
successors	O
became	O
a	O
legend	O
among	O
some	O
Soviet	O
programmers	O
and	O
computer	O
hobbyists	O
.	O
</s>
<s>
Some	O
Soviet	O
hackers	O
managed	O
to	O
modify	O
B3-34	B-Device
into	O
digital	O
multimeters	O
,	O
control	O
interfaces	O
for	O
model	O
railroads	O
,	O
added	O
tape	O
storage	O
devices	O
and	O
other	O
peripherals	O
.	O
</s>
<s>
Modern	O
Russian	O
calculators	O
and	O
,	O
designed	O
and	O
manufactured	O
in	O
Novosibirsk	O
since	O
2007	O
,	O
are	O
partially	O
backward	O
compatible	O
with	O
B3-34	B-Device
and	O
are	O
also	O
based	O
on	O
reverse	O
Polish	O
notation	O
.	O
</s>
