<s>
The	O
Kenbak-1	B-Device
is	O
considered	O
by	O
the	O
Computer	O
History	O
Museum	O
,	O
the	O
Computer	O
Museum	O
of	O
America	O
and	O
the	O
American	O
Computer	O
Museum	O
to	O
be	O
the	O
world	O
's	O
first	O
"	O
personal	B-Device
computer	I-Device
"	O
,	O
invented	O
by	O
John	B-Device
Blankenbaker	I-Device
(	O
born	O
1929	O
)	O
of	O
Kenbak	B-Device
Corporation	O
in	O
1970	O
,	O
and	O
first	O
sold	O
in	O
early	O
1971	O
.	O
</s>
<s>
Production	O
of	O
the	O
Kenbak-1	B-Device
stopped	O
in	O
1973	O
as	O
Kenbak	B-Device
failed	O
,	O
and	O
was	O
taken	O
over	O
by	O
CTI	O
Education	O
Products	O
,	O
Inc	O
.	O
CTI	O
rebranded	O
the	O
inventory	O
and	O
renamed	O
it	O
the	O
5050	O
,	O
though	O
sales	O
remained	O
elusive	O
.	O
</s>
<s>
Since	O
the	O
Kenbak-1	B-Device
was	O
invented	O
before	O
the	O
first	O
microprocessor	B-Architecture
,	O
the	O
machine	O
did	O
n't	O
have	O
a	O
one-chip	O
CPU	B-General_Concept
but	O
instead	O
was	O
based	O
purely	O
on	O
small-scale	O
integration	O
TTL	B-General_Concept
chips	O
.	O
</s>
<s>
The	O
8-bit	O
machine	O
offered	O
256bytes	O
of	O
memory	B-General_Concept
,	O
implemented	O
on	O
Intel	O
's	O
type	O
1404A	O
silicon	O
gate	O
MOS	O
shift	B-General_Concept
registers	I-General_Concept
.	O
</s>
<s>
The	O
clock	O
signal	O
period	O
was	O
1microsecond	O
(	O
equivalent	O
to	O
an	O
clock	O
speed	O
of	O
1MHz	O
)	O
,	O
but	O
the	O
program	O
speed	O
averaged	O
below	O
1000	O
instructions	O
per	O
second	O
due	O
many	O
clock	O
cycles	O
needed	O
for	O
each	O
operation	O
and	O
slow	O
access	O
to	O
serial	O
memory	B-General_Concept
.	O
</s>
<s>
The	O
machine	O
was	O
programmed	O
in	O
pure	O
machine	B-Language
code	I-Language
using	O
an	O
array	O
of	O
buttons	O
and	O
switches	O
.	O
</s>
<s>
Internally	O
,	O
the	O
Kenbak-1	B-Device
has	O
a	O
serial	B-Device
computer	I-Device
architecture	O
,	O
processing	O
one	O
bit	O
at	O
a	O
time	O
.	O
</s>
<s>
The	O
Kenbak-1	B-Device
has	O
a	O
total	O
of	O
nine	O
registers	O
.	O
</s>
<s>
All	O
are	O
memory	B-General_Concept
mapped	O
.	O
</s>
<s>
The	O
instructions	O
are	O
encoded	O
in	O
8	O
bits	O
,	O
with	O
a	O
possible	O
second	O
byte	B-Application
providing	O
an	O
immediate	O
value	O
or	O
address	O
.	O
</s>
<s>
Opcode	O
matrix	O
for	O
the	O
Kenbak-1	B-Device
instruction	O
set	O
High	O
octal	O
digits	O
Low	O
octal	O
digit	O
0	O
1	O
2	O
3	O
4	O
5	O
6	O
7	O
00HALTSFTR	O
A1SET	O
0	O
b0	O
XXXADD	O
A	O
#XXXADD	O
A	O
XXXADD	O
A	O
(	O
XXX	O
)	O
ADD	O
A	O
XXX	O
,	O
XADD	O
A	O
(	O
XXX	O
)	O
,	O
X	O
01HALTSFTR	O
A2SET	O
0	O
b1	O
XXXSUB	O
A	O
#XXXSUB	O
A	O
XXXSUB	O
A	O
(	O
XXX	O
)	O
SUB	O
A	O
XXX	O
,	O
XSUB	O
A	O
(	O
XXX	O
)	O
,	O
X	O
02HALTSFTR	O
A3SET	O
0	O
b2	O
XXXLOAD	O
A	O
#XXXLOAD	O
A	O
XXXLOAD	O
A	O
(	O
XXX	O
)	O
LOAD	O
A	O
XXX	O
,	O
XLOAD	O
A	O
(	O
XXX	O
)	O
,	O
X	O
03HALTSFTR	O
A4SET	O
0	O
b3	O
XXXSTORE	O
A	O
#XXXSTORE	O
A	O
XXXSTORE	O
A	O
(	O
XXX	O
)	O
STORE	O
A	O
XXX	O
,	O
XSTORE	O
A	O
(	O
XXX	O
)	O
,	O
X	O
04HALTSFTR	O
B1SET	O
0	O
b4	O
XXXJPD	O
A	O
≠0	O
XXXJPD	O
A	O
=	O
0	O
XXXJPD	O
A	O
<	O
0	O
XXXJPD	O
A	O
≥0	O
XXXJPD	O
A	O
>0	O
XXX	O
05HALTSFTR	O
B2SET	O
0	O
b5	O
XXXJPI	O
A	O
≠0	O
XXXJPI	O
A	O
=	O
0	O
XXXJPI	O
A	O
<	O
0	O
XXXJPI	O
A	O
≥0	O
XXXJPI	O
A	O
>0	O
XXX	O
06HALTSFTR	O
B3SET	O
0	O
b6	O
XXXJMD	O
A	O
≠0	O
XXXJMD	O
A	O
=	O
0	O
XXXJMD	O
A	O
<	O
0	O
XXXJMD	O
A	O
≥0	O
XXXJMD	O
A	O
>0	O
XXX	O
07HALTSFTR	O
B4SET	O
0	O
b7	O
XXXJMI	O
A	O
≠0	O
XXXJMI	O
A	O
=	O
0	O
XXXJMI	O
A	O
<	O
0	O
XXXJMI	O
A	O
≥0JMI	O
A	O
>0	O
XXX	O
10HALTROTR	O
A1SET	O
1	O
b0	O
XXXADD	O
B	O
#XXXADD	O
B	O
XXXADD	O
B	O
(	O
XXX	O
)	O
ADD	O
B	O
XXX	O
,	O
XADD	O
B	O
(	O
XXX	O
)	O
,	O
X	O
11HALTROTR	O
A2SET	O
1	O
b1	O
XXXSUB	O
B	O
#XXXSUB	O
B	O
XXXSUB	O
B	O
(	O
XXX	O
)	O
SUB	O
B	O
XXX	O
.	O
</s>
