<s>
TopoR	B-Algorithm
(	O
Topological	O
Router	B-Algorithm
)	O
is	O
an	O
EDA	O
program	O
developed	O
and	O
maintained	O
by	O
the	O
Russian	O
company	O
Eremex	B-Algorithm
.	O
</s>
<s>
It	O
is	O
dedicated	O
to	O
laying	O
out	O
a	O
printed	O
circuit	O
board	O
(	O
PCB	B-Language
)	O
.	O
</s>
<s>
It	O
features	O
a	O
powerful	O
autorouter	B-Algorithm
and	O
a	O
set	O
of	O
tools	O
intended	O
to	O
reduce	O
the	O
amount	O
of	O
effort	O
needed	O
for	O
manual	O
routing	B-Algorithm
of	O
a	O
PCB	B-Language
.	O
</s>
<s>
The	O
most	O
recognizable	O
feature	O
of	O
TopoR	B-Algorithm
is	O
the	O
absence	O
of	O
preferred	O
routing	B-Algorithm
directions	O
,	O
which	O
results	O
in	O
unusual	O
looking	O
PCBs	B-Language
.	O
</s>
<s>
1996	O
saw	O
the	O
release	O
of	O
the	O
first	O
version	O
of	O
a	O
topological	O
router	B-Algorithm
that	O
actually	O
came	O
to	O
be	O
used	O
by	O
industrial	O
enterprises	O
.	O
</s>
<s>
In	O
2002	O
,	O
the	O
FreeStyle	O
Router	B-Algorithm
(	O
FSR	O
)	O
by	O
Диал	O
Инжиниринг	O
(	O
"	O
Dial	O
Engineering	O
"	O
)	O
ran	O
under	O
DOS	B-Device
and	O
successfully	O
routed	O
dual-layer	O
boards	O
,	O
interfacing	O
with	O
P-CAD	B-Algorithm
.	O
</s>
<s>
This	O
early	O
router	B-Algorithm
showed	O
the	O
advantages	O
of	O
an	O
innovative	O
approach	O
to	O
routing	B-Algorithm
and	O
high	O
efficiency	O
of	O
the	O
models	O
,	O
algorithms	O
,	O
and	O
software	O
implementation	O
.	O
</s>
<s>
A	O
1.44MB	O
floppy	B-Device
disk	I-Device
was	O
enough	O
for	O
the	O
program	O
and	O
accompanying	O
examples	O
.	O
</s>
<s>
The	O
company	O
also	O
announced	O
plans	O
to	O
commercially	O
release	O
a	O
FreeStyle	O
Suite	O
for	O
Windows	B-Application
later	O
the	O
year	O
.	O
</s>
<s>
The	O
last	O
version	O
of	O
FSR	O
for	O
DOS	B-Device
,	O
consisting	O
of	O
the	O
router	B-Algorithm
named	O
SpeedWay	O
and	O
the	O
layout	O
editor	O
named	O
FreeStyle	O
was	O
version	O
1.6	O
as	O
of	O
2003-09-26/2003	O
-11-01	O
.	O
</s>
<s>
The	O
first	O
Windows	B-Application
version	O
of	O
the	O
topological	O
router	B-Algorithm
was	O
released	O
in	O
2001	O
and	O
renamed	O
to	O
TopoR	B-Algorithm
.	O
</s>
<s>
TopoR	B-Algorithm
1.03	O
was	O
available	O
on	O
2003-09-26	O
and	O
distributed	O
through	O
ElekTrade	O
( ЭлекТрейд	O
)	O
.	O
</s>
<s>
TopoR	B-Algorithm
was	O
developed	O
by	O
a	O
group	O
called	O
the	O
FreeStyleTeam	O
,	O
supervised	O
by	O
Sergey	O
J	O
.	O
Luzin	O
( Сергей	O
Юрьевич	O
Лузин	O
)	O
,	O
with	O
Oleg	O
B	O
.	O
Polubasov	O
( Олег	O
Борисович	O
Полубасов	O
)	O
as	O
initial	O
FSR	O
developer	O
,	O
as	O
well	O
as	O
Paul	O
I	O
.	O
Dmitriev	O
( Павел	O
Иванович	O
Дмитриев	O
)	O
,	O
Gevorg	O
S	O
.	O
Petrosyan	O
( Геворг	O
Самвелович	O
Петросян	O
)	O
,	O
Michael	O
S	O
.	O
Luzin	O
( Михаил	O
Сергеевич	O
Лузин	O
)	O
and	O
Andrew	O
A	O
.	O
Lysenko	O
( Андрей	O
Александрович	O
Лысенко	O
)	O
.	O
</s>
<s>
TopoR	B-Algorithm
4.0	O
added	O
support	O
to	O
import/export	O
DSN	O
design	O
and	O
SES	O
session	O
files	O
.	O
</s>
<s>
Since	O
TopoR	B-Algorithm
4.1	O
(	O
2008	O
)	O
the	O
software	O
is	O
further	O
developed	O
and	O
maintained	O
by	O
Eremex	B-Algorithm
,	I-Algorithm
Ltd	I-Algorithm
.	I-Algorithm
</s>
<s>
TopoR	B-Algorithm
can	O
be	O
used	O
as	O
an	O
external	O
autorouter	B-Algorithm
for	O
third-party	O
layout	O
editors	O
or	O
in	O
conjunction	O
with	O
Eremex	B-Algorithm
's	O
own	O
schematic	O
capture	O
and	O
layout	O
editor	O
Delta	B-Algorithm
Design	I-Algorithm
(	O
DD	B-Algorithm
)	O
.	O
</s>
<s>
TopoR	B-Algorithm
imports	O
input	O
in	O
Delta	B-Algorithm
Design	I-Algorithm
's	O
FST	O
format	O
,	O
as	O
Specctra-/ELECTRA	O
-compatible	O
DSN	O
design	O
files	O
,	O
or	O
in	O
P-CAD	B-Algorithm
PCB	I-Algorithm
ASCII	O
(	O
2000	O
,	O
2002	O
,	O
2004	O
)	O
,	O
PADS	O
PCB	B-Language
ASCII	O
(	O
3.5	O
,	O
4.0	O
,	O
5.0	O
,	O
2005.0	O
)	O
,	O
or	O
EAGLE	B-Language
BRD	O
XML	O
formats	O
(	O
6.x	O
)	O
.	O
</s>
<s>
The	O
resulting	O
boards	O
can	O
be	O
exported	O
into	O
Specctra/ELECTRA	O
SES	O
session	O
files	O
,	O
DXF	O
,	O
Gerber	O
,	O
P-CAD	B-Algorithm
PCB	I-Algorithm
ASCII	O
(	O
2000	O
,	O
2002	O
,	O
2004	O
)	O
,	O
PADS	O
PCB	B-Language
ASCII	O
(	O
3.5	O
,	O
4.0	O
,	O
5.0	O
,	O
2005.0	O
)	O
.	O
</s>
<s>
Routing	B-Algorithm
of	O
the	O
wiring	O
topology	O
is	O
done	O
automatically	O
and	O
flexibly	O
;	O
angles	O
are	O
not	O
limited	O
to	O
90°	O
and	O
45°	O
.	O
</s>
<s>
Efficient	O
use	O
of	O
PCB	B-Language
space	O
and	O
absence	O
of	O
preferred	O
routing	B-Algorithm
directions	O
in	O
layers	O
considerably	O
reduces	O
electromagnetic	O
crosstalk	O
.	O
</s>
<s>
TopoR	B-Algorithm
routes	O
all	O
connections	O
,	O
even	O
if	O
this	O
entails	O
violating	O
design	O
constraints	O
.	O
</s>
<s>
TopoR	B-Algorithm
simultaneously	O
optimizes	O
several	O
alternative	O
variants	O
of	O
the	O
layout	O
.	O
</s>
<s>
TopoR	B-Algorithm
has	O
an	O
automatic	O
component	O
placement	O
feature	O
.	O
</s>
<s>
TopoR	B-Algorithm
automatically	O
supports	O
trace	O
necking	O
,	O
that	O
is	O
,	O
it	O
reduces	O
the	O
width	O
of	O
a	O
wire	O
that	O
approaches	O
a	O
narrow	O
pad	O
(	O
or	O
one	O
with	O
a	O
diameter	O
that	O
is	O
less	O
than	O
the	O
width	O
of	O
the	O
wire	O
)	O
,	O
or	O
when	O
it	O
passes	O
through	O
bottlenecks	O
(	O
for	O
example	O
,	O
between	O
the	O
pads	O
of	O
a	O
component	O
)	O
.	O
</s>
<s>
TopoR	B-Algorithm
can	O
recognize	O
ball	B-Algorithm
grid	I-Algorithm
array	I-Algorithm
(	O
BGA	O
)	O
component	O
areas	O
and	O
apply	O
a	O
special	O
strategy	O
for	O
routing	B-Algorithm
them	O
.	O
</s>
<s>
This	O
helps	O
reduce	O
the	O
number	O
of	O
vias	O
,	O
the	O
density	O
of	O
connections	O
,	O
and	O
in	O
some	O
cases	O
the	O
number	O
of	O
routing	B-Algorithm
layers	O
.	O
</s>
<s>
A	O
special	O
algorithm	O
is	O
used	O
for	O
routing	B-Algorithm
single-layer	O
boards	O
minimizing	O
the	O
number	O
of	O
interlayer	O
junctions	O
or	O
to	O
find	O
a	O
single-layer	O
routing	B-Algorithm
.	O
</s>
<s>
The	O
layout	O
program	O
PCB	B-Language
of	O
the	O
gEDA	B-Application
suite	I-Application
includes	O
a	O
similar	O
topological	O
autorouter	B-Algorithm
named	O
Toporouter	O
,	O
which	O
was	O
written	O
by	O
Anthony	O
Blake	O
in	O
a	O
Google-funded	O
open	B-License
source	I-License
project	O
mentored	O
by	O
DJ	B-Application
Delorie	I-Application
in	O
2008	O
.	O
</s>
<s>
It	O
is	O
mostly	O
based	O
on	O
an	O
implementation	O
of	O
the	O
algorithms	O
described	O
in	O
Tal	O
Dayan	O
's	O
1997	O
PhD	O
thesis	O
,	O
"	O
Rubberband	O
based	O
topological	O
router	B-Algorithm
"	O
.	O
</s>
<s>
This	O
router	B-Algorithm
has	O
meanwhile	O
been	O
adapted	O
for	O
use	O
with	O
the	O
open-source	B-License
KiCad	B-Language
project	O
as	O
well	O
.	O
</s>
