<s>
Sargon	B-Application
(	O
or	O
SARGON	B-Application
)	O
is	O
a	O
line	O
of	O
chess-playing	O
software	O
for	O
personal	B-Device
computers	I-Device
.	O
</s>
<s>
The	O
original	O
SARGON	B-Application
from	O
1978	O
was	O
written	O
in	O
assembly	B-Language
language	I-Language
by	O
Dan	O
and	O
Kathleen	O
"	O
Kathe	O
"	O
Spracklen	O
for	O
the	O
Z80-based	O
Wavemate	O
Jupiter	O
III	O
.	O
</s>
<s>
SARGON	B-Application
was	O
introduced	O
at	O
the	O
1978	O
West	O
Coast	O
Computer	O
Faire	O
where	O
it	O
won	O
the	O
first	O
computer	B-Application
chess	I-Application
tournament	O
held	O
strictly	O
for	O
microcomputers	B-Architecture
,	O
with	O
a	O
score	O
of	O
5	O
–	O
0	O
.	O
</s>
<s>
Since	O
magnetic	O
media	O
were	O
not	O
widely	O
available	O
at	O
the	O
time	O
,	O
the	O
authors	O
placed	O
an	O
advert	O
in	O
Byte	O
magazine	O
selling	O
for	O
$15	O
photocopied	O
listings	O
that	O
would	O
work	O
in	O
any	O
Z80-based	O
microcomputer	B-Architecture
.	O
</s>
<s>
For	O
example	O
,	O
the	O
March	O
–	O
April	O
1979	O
issue	O
of	O
Recreational	O
Computing	O
describes	O
a	O
project	O
that	O
converted	O
Sargon	B-Application
to	O
an	O
8080	O
program	O
by	O
using	O
macros	O
.	O
</s>
<s>
When	O
magnetic	O
media	O
publishing	O
became	O
widely	O
available	O
,	O
a	O
US	O
Navy	O
petty	O
officer	O
,	O
Paul	O
Lohnes	O
,	O
ported	O
Sargon	B-Application
to	O
the	O
TRS-80	B-Device
,	O
altering	O
the	O
graphics	O
,	O
input	O
,	O
and	O
housekeeping	O
routines	O
but	O
leaving	O
the	O
Spracklens	O
 '	O
chess-playing	O
algorithm	O
intact	O
.	O
</s>
<s>
Paul	O
consulted	O
with	O
the	O
Spracklens	O
,	O
who	O
were	O
both	O
living	O
in	O
San	O
Diego	O
at	O
the	O
time	O
,	O
to	O
make	O
the	O
TRS-80	B-Device
version	O
an	O
instant	O
success	O
with	O
the	O
help	O
of	O
Hayden	O
Book	O
's	O
newly	O
established	O
software	O
division	O
:	O
Hayden	O
Software	O
.	O
</s>
<s>
Paul	O
was	O
not	O
involved	O
in	O
further	O
refinements	O
to	O
the	O
TRS-80	B-Device
version	O
due	O
to	O
his	O
reassignment	O
to	O
sea	O
duty	O
shortly	O
after	O
signing	O
the	O
deal	O
with	O
Hayden	O
Software	O
.	O
</s>
<s>
In	O
the	O
early	O
1980s	O
,	O
SARGON	B-Application
CHESS	I-Application
was	O
ported	O
to	O
the	O
Nascom	B-Operating_System
(	O
by	O
Bits	O
&	O
PCs	B-Device
,	O
1981	O
)	O
,	O
Exidy	B-Architecture
Sorcerer	I-Architecture
,	O
and	O
Sharp	B-Operating_System
MZ	I-Operating_System
80K	I-Operating_System
.	O
</s>
<s>
A	O
complete	O
rewrite	O
was	O
necessary	O
later	O
for	O
the	O
Apple	B-Device
II	I-Device
,	O
programmed	O
by	O
Kathleen	O
's	O
brother	O
Gary	O
Shannon	O
.	O
</s>
<s>
The	O
Spracklens	O
made	O
significant	O
improvements	O
on	O
the	O
original	O
program	O
and	O
released	O
Sargon	B-Application
II	I-Application
.	O
</s>
<s>
J	O
.	O
Mishcon	O
reviewed	O
Sargon	B-Application
II	I-Application
in	O
the	O
October	O
1980	O
issue	O
of	O
The	O
Space	O
Gamer	O
magazine	O
,	O
stating	O
that	O
the	O
program	O
beat	O
him	O
regularly	O
on	O
level	O
5	O
,	O
which	O
took	O
40	O
minutes	O
per	O
move	O
.	O
</s>
<s>
Sargon	B-Application
2.5	O
,	O
sold	O
as	O
a	O
ROM	O
module	O
for	O
the	O
Chafitz	O
Modular	O
Game	O
System	O
,	O
was	O
identical	O
to	O
Sargon	B-Application
II	I-Application
but	O
incorporated	O
pondering	O
.	O
</s>
<s>
Sargon	B-Application
3.0	O
finished	O
in	O
seventh	O
place	O
at	O
the	O
October	O
1979	O
North	O
American	O
Computer	B-Application
Chess	I-Application
Championship	O
.	O
</s>
<s>
The	O
competition	O
had	O
improved	O
,	O
but	O
3.0	O
drew	O
against	O
Cray	B-General_Concept
Blitz	I-General_Concept
and	O
easily	O
defeated	O
Mychess	O
,	O
its	O
main	O
microcomputer	B-Architecture
rival	O
.	O
</s>
<s>
In	O
December	O
,	O
3.0	O
easily	O
won	O
the	O
second	O
microcomputer	B-Architecture
championship	O
in	O
London	O
.	O
</s>
<s>
Sargon	B-Application
III	I-Application
was	O
a	O
complete	O
rewrite	O
.	O
</s>
<s>
Also	O
included	O
was	O
a	O
chess	B-Application
opening	O
repertoire	O
.	O
</s>
<s>
This	O
third	O
version	O
was	O
written	O
originally	O
for	O
the	O
6502	B-General_Concept
assembler	B-Language
.	O
</s>
<s>
In	O
1978	O
,	O
Sargon	B-Application
was	O
converted	O
to	O
Z80	B-General_Concept
neumonics/assembler	O
code	O
by	O
Paul	O
H	O
.	O
Lohnes	O
,	O
as	O
self	O
taught	O
computer	O
enthusiast	O
while	O
he	O
was	O
still	O
in	O
the	O
US	O
Navy	O
.	O
</s>
<s>
He	O
sold	O
the	O
publishing	O
rights	O
to	O
Hayden	O
Software	O
for	O
the	O
Radio	B-Device
Shack	I-Device
TRS-80	I-Device
platform	O
.	O
</s>
<s>
Apple	O
contacted	O
the	O
Spracklens	O
and	O
,	O
after	O
a	O
port	O
for	O
68000	B-Device
assembly	B-Language
,	O
Sargon	B-Application
III	I-Application
was	O
the	O
first	O
third-party	O
executable	O
software	O
for	O
the	O
Macintosh	B-Device
.	O
</s>
<s>
After	O
the	O
demise	O
of	O
Hayden	O
Software	O
,	O
later	O
chess	B-Application
programs	O
were	O
also	O
released	O
under	O
the	O
name	O
Sargon	B-Application
,	O
including	O
Sargon	B-Application
4	I-Application
(	O
Spinnaker	O
Software	O
)	O
,	O
Sargon	B-Application
V	O
(	O
Activision	O
)	O
and	O
a	O
CD-i	B-Device
title	O
simply	O
named	O
Sargon	B-Application
Chess	I-Application
.	O
</s>
<s>
The	O
Spracklens	O
concurrently	O
wrote	O
the	O
engines	O
for	O
the	O
dedicated	O
chess	B-Application
computers	I-Application
produced	O
by	O
Fidelity	O
Electronics	O
,	O
which	O
won	O
the	O
first	O
four	O
World	O
Microcomputer	B-Architecture
Chess	B-Application
Championships	O
.	O
</s>
<s>
The	O
three-time	O
world	O
chess	B-Application
champion	O
Mikhail	O
Botvinnik	O
played	O
a	O
game	O
with	O
Sargon	B-Application
in	O
1983	O
at	O
Hamburg	O
.	O
</s>
<s>
Botvinnik	O
himself	O
was	O
also	O
involved	O
in	O
chess	B-Application
program	O
development	O
.	O
</s>
