<s>
The	O
MC6800	B-Device
microprocessor	O
was	O
part	O
of	O
the	O
M6800	B-Device
Microcomputer	I-Device
System	I-Device
(	O
latter	O
dubbed	O
68xx	B-Device
)	O
that	O
also	O
included	O
serial	O
and	O
parallel	O
interface	O
ICs	O
,	O
RAM	B-Architecture
,	O
ROM	B-Device
and	O
other	O
support	O
chips	O
.	O
</s>
<s>
A	O
significant	O
design	O
feature	O
was	O
that	O
the	O
M6800	B-Device
family	I-Device
of	O
ICs	O
required	O
only	O
a	O
single	O
five-volt	O
power	O
supply	O
at	O
a	O
time	O
when	O
most	O
other	O
microprocessors	O
required	O
three	O
voltages	O
.	O
</s>
<s>
The	O
M6800	B-Device
Microcomputer	I-Device
System	I-Device
was	O
announced	O
in	O
March	O
1974	O
and	O
was	O
in	O
full	O
production	O
by	O
the	O
end	O
of	O
that	O
year	O
.	O
</s>
<s>
It	O
has	O
72	O
instructions	O
with	O
seven	O
addressing	O
modes	O
for	O
a	O
total	O
of	O
197	O
opcodes	B-Language
.	O
</s>
<s>
The	O
original	O
MC6800	B-Device
could	O
have	O
a	O
clock	O
frequency	O
of	O
up	O
to	O
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
ICs	O
,	O
Motorola	O
also	O
provided	O
a	O
complete	O
assembly	B-Language
language	I-Language
development	O
system	O
.	O
</s>
<s>
The	O
customer	O
could	O
use	O
the	O
software	O
on	O
a	O
remote	O
timeshare	B-General_Concept
computer	O
or	O
on	O
an	O
in-house	O
minicomputer	B-Architecture
system	O
.	O
</s>
<s>
The	O
Motorola	O
EXORciser	O
was	O
a	O
desktop	B-Device
computer	I-Device
built	O
with	O
the	O
M6800	B-Device
ICs	O
that	O
could	O
be	O
used	O
for	O
prototyping	B-Application
and	O
debugging	O
new	O
designs	O
.	O
</s>
<s>
An	O
expansive	O
documentation	O
package	O
included	O
datasheets	O
on	O
all	O
ICs	O
,	O
two	O
assembly	B-Language
language	I-Language
programming	O
manuals	O
,	O
and	O
a	O
700-page	O
application	O
manual	O
that	O
showed	O
how	O
to	O
design	O
a	O
point-of-sale	O
terminal	O
(	O
a	O
computerized	O
cash	O
register	O
)	O
around	O
the	O
6800	O
.	O
</s>
<s>
The	O
6800	O
was	O
popular	O
in	O
computer	B-Device
peripherals	I-Device
,	O
test	O
equipment	O
applications	O
and	O
point-of-sale	O
terminals	O
.	O
</s>
<s>
The	O
MC6802	B-Device
,	O
introduced	O
in	O
1977	O
,	O
included	O
128	O
bytes	O
of	O
RAM	B-Architecture
and	O
an	O
internal	O
clock	O
oscillator	O
on	O
chip	O
.	O
</s>
<s>
The	O
MC6801	O
and	O
MC6805	O
included	O
RAM	B-Architecture
,	O
ROM	B-Device
and	O
I/O	O
on	O
a	O
single	O
chip	O
and	O
were	O
popular	O
in	O
automotive	O
applications	O
.	O
</s>
<s>
The	O
Motorola	B-Device
6809	I-Device
was	O
an	O
updated	O
compatible	O
design	O
.	O
</s>
<s>
They	O
began	O
commercial	O
production	O
of	O
transistors	B-Application
at	O
a	O
new	O
US	O
$1.5	O
million	O
facility	O
in	O
Phoenix	O
in	O
1955	O
.	O
</s>
<s>
Motorola	O
's	O
transistors	B-Application
and	O
integrated	O
circuits	O
were	O
used	O
in-house	O
for	O
their	O
communication	O
,	O
military	O
,	O
automotive	O
and	O
consumer	O
products	O
and	O
they	O
were	O
also	O
sold	O
to	O
other	O
companies	O
.	O
</s>
<s>
In	O
the	O
early	O
1970s	O
Motorola	O
started	O
a	O
project	O
that	O
developed	O
their	O
first	O
microprocessor	O
,	O
the	O
MC6800	B-Device
.	O
</s>
<s>
This	O
was	O
followed	O
by	O
single-chip	O
microcontrollers	B-Architecture
such	O
as	O
the	O
MC6801	O
and	O
MC6805	O
.	O
</s>
<s>
Tom	O
Bennett	O
had	O
a	O
background	O
in	O
industrial	O
controls	O
and	O
had	O
worked	O
for	O
Victor	O
Comptometer	O
in	O
the	O
1960s	O
designing	O
the	O
first	O
electronic	O
calculator	O
to	O
use	O
MOS	O
ICs	O
,	O
the	O
Victor	B-Device
3900	I-Device
.	O
</s>
<s>
In	O
May	O
1969	O
Ted	O
Hoff	O
showed	O
Bennett	O
early	O
diagrams	O
of	O
the	O
Intel	B-General_Concept
4004	I-General_Concept
to	O
see	O
if	O
it	O
would	O
meet	O
their	O
calculator	O
needs	O
.	O
</s>
<s>
In	O
September	O
1975	O
Robert	O
H	B-Device
.	O
Cushman	O
,	O
EDN	O
magazine	O
's	O
microprocessor	O
editor	O
,	O
interviewed	O
Chuck	O
Peddle	O
about	O
MOS	B-Architecture
Technology	I-Architecture
's	O
new	O
6502	B-General_Concept
microprocessor	I-General_Concept
.	O
</s>
<s>
LaVell	O
had	O
previously	O
worked	O
for	O
Collins	O
Radio	O
on	O
their	O
C8500	O
computer	O
that	O
was	O
built	O
with	O
small	O
scale	O
ECL	B-General_Concept
ICs	O
.	O
</s>
<s>
Some	O
of	O
these	O
blocks	O
were	O
implemented	O
in	O
the	O
initial	O
M6800	B-Device
release	O
and	O
more	O
were	O
added	O
over	O
the	O
next	O
few	O
years	O
.	O
</s>
<s>
To	O
evaluate	O
the	O
6800	O
architecture	O
while	O
the	O
chip	O
was	O
being	O
designed	O
,	O
LaVell	O
's	O
team	O
built	O
an	O
equivalent	O
circuit	O
using	O
451	O
small	O
scale	O
TTL	B-General_Concept
ICs	O
on	O
five	O
10	O
by	O
10	O
inch	O
(	O
25	O
by	O
25cm	O
)	O
circuit	O
boards	O
.	O
</s>
<s>
Typical	O
n-channel	O
MOS	O
IC	O
's	O
required	O
three	O
power	O
supplies	O
:	O
-5	O
volts	O
,	O
+5	O
volts	O
and	O
+12	O
volts	O
.	O
</s>
<s>
The	O
M6800	B-Device
family	I-Device
was	O
to	O
use	O
only	O
one	O
,	O
+5	O
volts	O
.	O
</s>
<s>
It	O
was	O
easy	O
to	O
eliminate	O
the	O
−5	O
volt	O
supply	O
by	O
using	O
an	O
internal	O
voltage	O
inverter	O
,	O
but	O
the	O
enhancement-mode	B-Algorithm
logic	O
also	O
needed	O
a	O
supply	O
of	O
10	O
to	O
12	O
volts	O
.	O
</s>
<s>
Later	O
Orgill	O
would	O
design	O
the	O
MOS	B-Architecture
Technology	I-Architecture
6501	B-General_Concept
microprocessor	O
that	O
was	O
socket	O
compatible	O
with	O
the	O
6800	O
.	O
</s>
<s>
Lattin	O
and	O
Frank	O
Jenkins	O
had	O
both	O
attended	O
UC	O
Berkeley	O
and	O
studied	O
computer	O
circuit	O
simulators	O
under	O
Donald	O
Pederson	O
,	O
the	O
designer	O
of	O
the	O
SPICE	B-Protocol
circuit	O
simulator	O
.	O
</s>
<s>
The	O
group	O
published	O
a	O
technical	O
paper	O
,	O
"	O
MOS-device	O
modeling	O
for	O
computer	O
implementation	O
"	O
in	O
1973	O
describing	O
a	O
"	O
5-V	O
single-supply	O
n-channel	O
technology	O
"	O
operating	O
at	O
1MHz	O
.	O
</s>
<s>
They	O
could	O
simulate	O
a	O
50	O
MOSFET	B-Architecture
circuit	O
on	O
an	O
IBM	O
370/165	O
mainframe	O
computer	O
.	O
</s>
<s>
He	O
also	O
worked	O
the	O
application	O
group	O
that	O
was	O
defining	O
the	O
M6800	B-Device
system	O
.	O
</s>
<s>
After	O
this	O
training	O
year	O
,	O
he	O
was	O
assigned	O
to	O
the	O
6820	O
Peripheral	B-General_Concept
Interface	I-General_Concept
Adapter	I-General_Concept
(	O
PIA	O
)	O
development	O
team	O
.	O
</s>
<s>
Mensch	O
was	O
a	O
major	O
contributor	O
to	O
the	O
design	O
of	O
this	O
chip	O
and	O
received	O
a	O
patent	O
on	O
the	O
IC	O
layout	O
and	O
was	O
named	O
as	O
a	O
co-inventor	O
of	O
seven	O
other	O
M6800	B-Device
system	O
patents	O
.	O
</s>
<s>
Later	O
Mensch	O
would	O
design	O
the	O
MOS	B-General_Concept
Technology	I-General_Concept
6502	I-General_Concept
microprocessor	O
.	O
</s>
<s>
He	O
is	O
listed	O
as	O
an	O
inventor	O
on	O
eighteen	O
6800	O
patents	O
but	O
is	O
best	O
known	O
for	O
a	O
computer	O
program	O
,	O
MIKBUG	B-Device
.	O
</s>
<s>
This	O
was	O
a	O
monitor	B-Application
for	O
a	O
6800	O
computer	O
system	O
that	O
allowed	O
the	O
user	O
to	O
examine	O
the	O
contents	O
of	O
RAM	B-Architecture
and	O
to	O
save	O
or	O
load	O
programs	O
to	O
tape	O
.	O
</s>
<s>
This	O
512	O
byte	O
program	O
occupied	O
half	O
of	O
an	O
MCM6830	O
ROM	B-Device
.	O
</s>
<s>
This	O
ROM	B-Device
was	O
used	O
in	O
the	O
Motorola	O
MEK6800	O
design	O
evaluation	O
kit	O
and	O
early	O
hobby	O
computer	O
kits	O
.	O
</s>
<s>
Wiles	O
stayed	O
with	O
Motorola	O
,	O
moved	O
to	O
Austin	O
and	O
helped	O
design	O
the	O
MC6801	O
microcontroller	B-Architecture
that	O
was	O
released	O
in	O
1978	O
.	O
</s>
<s>
In	O
August	O
1974	O
Chuck	O
Peddle	O
left	O
Motorola	O
and	O
joined	O
a	O
small	O
semiconductor	O
company	O
in	O
Pennsylvania	O
,	O
MOS	B-Architecture
Technology	I-Architecture
.	O
</s>
<s>
The	O
Motorola	B-Device
6800	I-Device
and	O
the	O
Intel	B-General_Concept
8080	I-General_Concept
were	O
designed	O
at	O
the	O
same	O
time	O
and	O
were	O
similar	O
in	O
function	O
.	O
</s>
<s>
The	O
8080	B-General_Concept
was	O
an	O
extension	O
and	O
enhancement	O
of	O
the	O
Intel	O
8008	O
,	O
which	O
in	O
turn	O
was	O
an	O
LSI	O
implementation	O
of	O
the	O
TTL-based	O
CPU	O
design	O
used	O
in	O
the	O
Datapoint	B-Device
2200	I-Device
.	O
</s>
<s>
The	O
6800	O
architecture	O
was	O
a	O
TTL-compatible	O
LSI	O
design	O
modeled	O
after	O
the	O
DEC	B-Device
PDP-11	I-Device
processor	O
.	O
</s>
<s>
The	O
6800	O
had	O
an	O
8-bit	O
bidirectional	O
data	O
bus	O
,	O
a	O
16-bit	O
address	O
bus	O
that	O
could	O
address	O
64KB	O
of	O
memory	O
,	O
and	O
came	O
in	O
a	O
40-pin	O
DIP	B-Algorithm
package	O
.	O
</s>
<s>
The	O
direct	O
addressing	O
mode	O
,	O
often	O
known	O
as	O
the	O
zero	B-General_Concept
page	I-General_Concept
in	O
other	O
processors	O
,	O
allowed	O
fast	O
access	O
to	O
the	O
first	O
256bytes	O
of	O
memory	O
.	O
</s>
<s>
I/O	O
devices	O
were	O
addressed	O
as	O
memory	O
so	O
there	O
were	O
no	O
special	O
I/O	O
instructions	O
.	O
</s>
<s>
The	O
6800	O
had	O
a	O
three-state	O
control	O
that	O
would	O
disable	O
the	O
address	O
bus	O
to	O
allow	O
another	O
device	O
direct	B-General_Concept
memory	I-General_Concept
access	I-General_Concept
.	O
</s>
<s>
For	O
instance	O
,	O
a	O
floppy	B-Device
disk	I-Device
controller	O
could	O
load	O
data	O
into	O
memory	O
without	O
requiring	O
any	O
support	O
from	O
the	O
CPU	O
.	O
</s>
<s>
Other	O
divisions	O
in	O
Motorola	O
developed	O
components	O
for	O
the	O
M6800	B-Device
family	I-Device
.	O
</s>
<s>
The	O
Components	O
Products	O
Department	O
designed	O
the	O
MC6870	O
two-phase	O
clock	O
IC	O
,	O
and	O
the	O
Memory	O
Products	O
group	O
provided	O
a	O
full	O
line	O
of	O
ROMs	O
and	O
RAMs	B-Architecture
.	O
</s>
<s>
Motorola	O
could	O
supply	O
every	O
IC	O
,	O
transistor	B-Application
,	O
and	O
diode	O
necessary	O
to	O
build	O
an	O
MC6800-based	O
computer	O
.	O
</s>
<s>
The	O
first-generation	O
metal	B-Architecture
–	I-Architecture
oxide	I-Architecture
–	I-Architecture
semiconductor	I-Architecture
(	O
MOS	O
)	O
chips	O
used	O
p-channel	O
field-effect	O
transistors	B-Application
,	O
known	O
as	O
p-channel	O
MOSFETs	B-Architecture
(	O
p-channel	O
describes	O
the	O
configuration	O
of	O
the	O
transistor	B-Application
)	O
.	O
</s>
<s>
These	O
ICs	O
were	O
used	O
in	O
calculators	O
and	O
in	O
the	O
first	O
microprocessor	O
,	O
the	O
Intel	B-General_Concept
4004	I-General_Concept
.	O
</s>
<s>
They	O
were	O
easy	O
to	O
produce	O
but	O
were	O
slow	O
and	O
difficult	O
to	O
interface	O
to	O
the	O
popular	O
TTL	B-General_Concept
digital	O
logic	O
ICs	O
.	O
</s>
<s>
An	O
n-channel	O
MOS	O
integrated	O
circuit	O
could	O
operate	O
two	O
or	O
three	O
times	O
faster	O
and	O
was	O
compatible	O
with	O
TTL	B-General_Concept
.	O
</s>
<s>
Motorola	O
did	O
not	O
have	O
an	O
n-channel	O
MOS	O
production	O
capability	O
and	O
had	O
to	O
develop	O
one	O
for	O
the	O
6800	O
family	O
.	O
</s>
<s>
Motorola	O
's	O
n-channel	O
MOS	O
test	O
integrated	O
circuits	O
were	O
complete	O
in	O
late	O
1971	O
and	O
these	O
indicated	O
the	O
clock	O
rate	O
would	O
be	O
limited	O
to	O
1MHz	O
.	O
</s>
<s>
These	O
used	O
"	O
enhancement-mode	B-Algorithm
"	O
MOS	B-Architecture
transistors	I-Architecture
.	O
</s>
<s>
There	O
was	O
a	O
newer	O
fabrication	O
technology	O
that	O
used	O
"	O
depletion-mode	B-Algorithm
"	O
MOS	B-Architecture
transistors	I-Architecture
as	O
loads	O
,	O
which	O
would	O
allow	O
smaller	O
and	O
faster	O
circuits	O
(	O
this	O
was	O
also	O
known	O
as	O
depletion-load	B-Algorithm
nMOS	I-Algorithm
)	O
.	O
</s>
<s>
The	O
"	O
depletion-mode	B-Algorithm
"	O
processing	O
required	O
extra	O
steps	O
so	O
Motorola	O
decided	O
to	O
stay	O
with	O
"	O
enhancement-mode	B-Algorithm
"	O
for	O
the	O
new	O
single-supply-voltage	O
design	O
.	O
</s>
<s>
In	O
the	O
1970s	O
,	O
semiconductors	O
were	O
fabricated	O
on	O
3	O
inch	O
(	O
75mm	O
)	O
diameter	O
silicon	B-Architecture
wafers	I-Architecture
.	O
</s>
<s>
Each	O
wafer	B-Architecture
could	O
produce	O
100	O
to	O
200	O
integrated	O
circuit	O
chips	O
or	O
dies	O
.	O
</s>
<s>
Processing	O
wafers	B-Architecture
required	O
multiple	O
steps	O
and	O
flaws	O
would	O
appear	O
at	O
various	O
locations	O
on	O
the	O
wafer	B-Architecture
during	O
each	O
step	O
.	O
</s>
<s>
At	O
180	O
mils	O
,	O
a	O
wafer	B-Architecture
will	O
hold	O
about	O
190	O
chips	O
,	O
212	O
mils	O
reduces	O
that	O
to	O
140	O
chips	O
.	O
</s>
<s>
At	O
this	O
size	O
the	O
yield	O
may	O
be	O
20%	O
or	O
28	O
chips	O
per	O
wafer	B-Architecture
.	O
</s>
<s>
The	O
Motorola	O
1975	O
annual	O
report	O
highlights	O
the	O
new	O
MC6800	B-Device
microprocessor	O
but	O
has	O
several	O
paragraphs	O
on	O
the	O
"	O
MOS	O
yield	O
problems.	O
"	O
</s>
<s>
The	O
yield	O
problem	O
was	O
solved	O
with	O
a	O
design	O
revision	O
started	O
in	O
1975	O
to	O
use	O
depletion	B-Algorithm
mode	I-Algorithm
in	O
the	O
M6800	B-Device
family	I-Device
devices	O
.	O
</s>
<s>
The	O
March	O
7	O
,	O
1974	O
issue	O
of	O
Electronics	O
had	O
a	O
two-page	O
story	O
on	O
the	O
Motorola	O
MC6800	B-Device
microprocessor	O
along	O
with	O
the	O
MC6820	O
Peripheral	B-General_Concept
Interface	I-General_Concept
Adapter	I-General_Concept
,	O
the	O
MC6850	O
Asynchronous	O
Communications	O
Interface	O
Adapter	O
,	O
the	O
MCM6810	O
128	O
byte	O
RAM	B-Architecture
and	O
the	O
MCM6830	O
1024	O
byte	O
ROM	B-Device
.	O
</s>
<s>
This	O
issue	O
also	O
had	O
an	O
article	O
introducing	O
the	O
Intel	B-General_Concept
8080	I-General_Concept
.	O
</s>
<s>
Both	O
the	O
Intel	B-General_Concept
8080	I-General_Concept
and	O
the	O
Motorola	O
MC6800	B-Device
processors	O
began	O
layout	O
around	O
December	O
1972	O
.	O
</s>
<s>
The	O
first	O
working	O
8080	B-General_Concept
chips	O
were	O
produced	O
January	O
1974	O
and	O
the	O
first	O
public	O
announcement	O
was	O
in	O
February	O
1974	O
.	O
</s>
<s>
The	O
8080	B-General_Concept
used	O
same	O
three	O
voltage	O
N-channel	O
MOS	O
process	O
as	O
Intel	O
's	O
existing	O
memory	O
chips	O
allowing	O
full	O
production	O
to	O
begin	O
that	O
April	O
.	O
</s>
<s>
The	O
first	O
working	O
MC6800	B-Device
chips	O
were	O
produced	O
in	O
February	O
1974	O
and	O
engineering	O
samples	O
were	O
given	O
to	O
select	O
customers	O
.	O
</s>
<s>
Hewlett-Packard	O
in	O
Loveland	O
,	O
Colorado	O
wanted	O
the	O
MC6800	B-Device
for	O
a	O
new	O
desktop	O
calculator	O
and	O
had	O
a	O
prototype	B-Application
system	O
working	O
by	O
June	O
.	O
</s>
<s>
The	O
MC6800	B-Device
used	O
a	O
new	O
single-voltage	O
N-channel	O
MOS	O
process	O
that	O
proved	O
to	O
be	O
very	O
difficult	O
to	O
implement	O
.	O
</s>
<s>
The	O
M6800	B-Device
microcomputer	I-Device
system	I-Device
was	O
finally	O
in	O
production	O
by	O
November	O
1974	O
.	O
</s>
<s>
(	O
The	O
IBM	B-Application
System/360	I-Application
was	O
a	O
well-known	O
computer	O
at	O
this	O
time	O
.	O
)	O
</s>
<s>
The	O
kit	O
included	O
all	O
six	O
chips	O
in	O
the	O
M6800	B-Device
family	I-Device
plus	O
application	O
and	O
programming	O
manuals	O
.	O
</s>
<s>
The	O
price	O
of	O
a	O
single	O
MC6800	B-Device
microprocessor	O
was	O
$175	O
.	O
</s>
<s>
Link	O
Young	O
was	O
the	O
product	O
marketer	O
that	O
developed	O
the	O
total	O
system	O
approach	O
for	O
the	O
M6800	B-Device
family	I-Device
release	O
.	O
</s>
<s>
The	O
software	O
development	O
tools	O
were	O
available	O
on	O
remote	O
time-sharing	B-General_Concept
computers	O
or	O
the	O
source	O
code	O
was	O
available	O
so	O
the	O
customer	O
could	O
use	O
an	O
in-house	O
computer	O
system	O
.	O
</s>
<s>
The	O
software	O
that	O
would	O
run	O
on	O
a	O
microprocessor	O
system	O
was	O
typically	O
written	O
in	O
assembly	B-Language
language	I-Language
.	O
</s>
<s>
The	O
development	O
system	O
consisted	O
of	O
a	O
text	O
editor	O
,	O
assembler	B-Language
and	O
a	O
simulator	O
.	O
</s>
<s>
The	O
hardware	O
development	O
was	O
a	O
desktop	B-Device
computer	I-Device
built	O
with	O
M6800	B-Device
family	I-Device
CPU	O
and	O
peripherals	B-Device
known	O
as	O
the	O
EXORcisor	O
.	O
</s>
<s>
The	O
principal	O
design	O
effort	O
on	O
the	O
M6800	B-Device
family	I-Device
was	O
complete	O
in	O
mid-1974	O
,	O
and	O
many	O
engineers	O
left	O
the	O
group	O
or	O
the	O
company	O
.	O
</s>
<s>
In	O
August	O
1974	O
Chuck	O
Peddle	O
left	O
Motorola	O
and	O
joined	O
a	O
small	O
semiconductor	O
company	O
in	O
Pennsylvania	O
,	O
MOS	B-Architecture
Technology	I-Architecture
.	O
</s>
<s>
Peddle	O
's	O
group	O
at	O
MOS	B-Architecture
Technology	I-Architecture
developed	O
two	O
new	O
microprocessors	O
that	O
were	O
compatible	O
with	O
the	O
Motorola	O
peripheral	O
chips	O
like	O
the	O
6820	O
PIA	O
.	O
</s>
<s>
Rod	O
Orgill	O
designed	O
the	O
MCS6501	O
processor	O
that	O
would	O
plug	O
into	O
a	O
MC6800	B-Device
socket	O
and	O
Bill	O
Mensch	O
did	O
the	O
MCS6502	O
that	O
had	O
the	O
clock	O
generation	O
circuit	O
on	O
chip	O
.	O
</s>
<s>
The	O
address	O
buffers	O
did	O
not	O
have	O
a	O
three-state	O
mode	O
for	O
Direct	B-General_Concept
Memory	I-General_Concept
Access	I-General_Concept
(	O
DMA	O
)	O
data	O
transfers	O
.	O
</s>
<s>
Chuck	O
Peddle	O
was	O
a	O
very	O
effective	O
spokesman	O
and	O
the	O
MOS	B-Architecture
Technology	I-Architecture
microprocessors	O
were	O
extensively	O
covered	O
in	O
the	O
trade	O
press	O
.	O
</s>
<s>
Advertisements	O
for	O
the	O
6501	B-General_Concept
appeared	O
in	O
several	O
publications	O
the	O
first	O
week	O
of	O
August	O
1975	O
.	O
</s>
<s>
The	O
6501	B-General_Concept
would	O
be	O
for	O
sale	O
at	O
the	O
WESCON	O
trade	O
show	O
in	O
San	O
Francisco	O
,	O
September	O
16	O
–	O
19	O
,	O
1975	O
,	O
for	O
each	O
.	O
</s>
<s>
In	O
September	O
1975	O
the	O
advertisements	O
included	O
both	O
the	O
6501	B-General_Concept
and	O
the	O
6502	B-General_Concept
microprocessors	I-General_Concept
.	O
</s>
<s>
The	O
6502	B-General_Concept
would	O
only	O
cost	O
.	O
</s>
<s>
Motorola	O
responded	O
to	O
MOS	B-Architecture
Technology	I-Architecture
's	O
microprocessor	O
by	O
immediately	O
reducing	O
the	O
single-unit	O
price	O
of	O
the	O
6800	O
microprocessor	O
from	O
to	O
and	O
then	O
suing	O
MOS	B-Architecture
Technology	I-Architecture
in	O
November	O
1975	O
.	O
</s>
<s>
Motorola	O
claimed	O
that	O
the	O
eight	O
former	O
Motorola	O
engineers	O
used	O
technical	O
information	O
developed	O
at	O
Motorola	O
in	O
the	O
design	O
of	O
the	O
6501	B-General_Concept
and	O
6502	B-General_Concept
microprocessors	I-General_Concept
.	O
</s>
<s>
MOS	B-Architecture
Technology	I-Architecture
's	O
other	O
business	O
,	O
calculator	O
chips	O
,	O
was	O
declining	O
due	O
to	O
a	O
price	O
war	O
with	O
Texas	O
Instruments	O
so	O
their	O
financial	O
backer	O
,	O
Allen-Bradley	O
,	O
decided	O
to	O
limit	O
the	O
possible	O
losses	O
and	O
sold	O
the	O
assets	O
of	O
MOS	B-Architecture
Technology	I-Architecture
back	O
to	O
the	O
founders	O
.	O
</s>
<s>
The	O
lawsuit	O
was	O
settled	O
in	O
April	O
1976	O
with	O
MOS	B-Architecture
Technology	I-Architecture
dropping	O
the	O
6501	B-General_Concept
chip	O
that	O
would	O
plug	O
into	O
a	O
Motorola	B-Device
6800	I-Device
socket	O
and	O
licensing	O
Motorola	O
's	O
peripheral	O
chips	O
.	O
</s>
<s>
The	O
MOS	B-Architecture
Technology	I-Architecture
vs.	O
Motorola	O
lawsuit	O
has	O
developed	O
a	O
David	O
and	O
Goliath	O
narrative	O
over	O
the	O
years	O
.	O
</s>
<s>
This	O
design	O
used	O
depletion-mode	B-Algorithm
technology	O
and	O
was	O
known	O
internally	O
as	O
the	O
MC6800D	O
.	O
</s>
<s>
The	O
transistor	B-Application
count	O
went	O
from	O
4000	O
to	O
5000	O
but	O
the	O
die	O
area	O
was	O
reduced	O
from	O
29.0mm2	O
to	O
16.5mm2	O
(	O
allowing	O
the	O
price	O
of	O
the	O
CPU	O
to	O
be	O
lowered	O
to	O
$35	O
)	O
.	O
</s>
<s>
The	O
other	O
chips	O
in	O
the	O
M6800	B-Device
family	I-Device
were	O
also	O
redesigned	O
to	O
use	O
depletion-mode	B-Algorithm
technology	O
.	O
</s>
<s>
The	O
Peripheral	B-General_Concept
Interface	I-General_Concept
Adapter	I-General_Concept
had	O
a	O
slight	O
change	O
in	O
the	O
electrical	O
characteristics	O
of	O
the	O
I/O	O
pins	O
so	O
the	O
MC6820	O
became	O
the	O
MC6821	O
.	O
</s>
<s>
The	O
MC6875	O
came	O
in	O
a	O
16-pin	O
dip	B-Algorithm
package	O
and	O
could	O
use	O
quartz	O
crystal	O
or	O
a	O
resistor	O
capacitor	O
network	O
.	O
</s>
<s>
Another	O
project	O
was	O
incorporating	O
128	O
bytes	O
of	O
RAM	B-Architecture
and	O
the	O
clock	O
generator	O
on	O
a	O
single	O
11,000	O
-transistor	O
chip	O
.	O
</s>
<s>
The	O
MC6802	B-Device
microprocessor	O
was	O
released	O
in	O
March	O
1977	O
.	O
</s>
<s>
The	O
companion	O
MC6846	O
chip	O
had	O
2048	O
byte	O
ROM	B-Device
,	O
an	O
8-bit	O
bidirectional	O
port	O
and	O
a	O
programmable	O
timer	O
.	O
</s>
<s>
The	O
internal	O
128	O
byte	O
RAM	B-Architecture
could	O
be	O
disabled	O
by	O
grounding	O
a	O
pin	O
and	O
devices	O
with	O
defective	O
RAM	B-Architecture
were	O
sold	O
as	O
a	O
MC6808	O
.	O
</s>
<s>
The	O
MC6844	O
Direct	B-General_Concept
Memory	I-General_Concept
Access	I-General_Concept
Controller	O
could	O
transfer	O
data	O
from	O
an	O
I/O	O
controller	O
to	O
RAM	B-Architecture
without	O
loading	O
down	O
the	O
MC6800	B-Device
microprocessor	O
.	O
</s>
<s>
The	O
MC6845	B-General_Concept
CRT	O
Controller	O
(	O
CRTC	O
)	O
provided	O
the	O
control	O
logic	O
for	O
a	O
character	O
based	O
computer	O
terminal	O
.	O
</s>
<s>
The	O
6845	B-General_Concept
had	O
support	O
for	O
a	O
light	B-Device
pen	I-Device
,	O
an	O
alternative	O
to	O
a	O
computer	O
mouse	O
.	O
</s>
<s>
The	O
MC6845	B-General_Concept
was	O
a	O
very	O
popular	O
chip	O
:	O
it	O
was	O
even	O
used	O
in	O
the	O
original	O
IBM	B-Device
Monochrome	I-Device
Display	I-Device
Adapter	I-Device
and	O
the	O
original	O
IBM	B-Device
Color	I-Device
Graphics	I-Device
Adapter	I-Device
for	O
the	O
IBM	B-Device
PC	I-Device
and	O
successors	O
,	O
where	O
the	O
6845	B-General_Concept
was	O
used	O
with	O
an	O
Intel	O
8088	O
CPU	O
.	O
</s>
<s>
During	O
the	O
time	O
of	O
cold	O
war	O
technology	O
embargoes	O
,	O
a	O
6845	B-General_Concept
clone	O
named	O
CM607	O
was	O
produced	O
in	O
Bulgaria	O
.	O
</s>
<s>
The	O
later	O
IBM	B-Device
Enhanced	I-Device
Graphics	I-Device
Adapter	I-Device
(	O
EGA	B-Device
)	O
card	O
contained	O
a	O
custom	O
IBM	O
chip	O
(	O
the	O
EGA	B-Device
CRTC	O
)	O
that	O
replaced	O
the	O
Motorola	B-General_Concept
6845	I-General_Concept
,	O
adding	O
many	O
enhancements	O
,	O
in	O
a	O
mostly-compatible	O
way	O
.	O
</s>
<s>
The	O
IBM	B-Protocol
Video	I-Protocol
Graphics	I-Protocol
Array	I-Protocol
(	O
VGA	B-Protocol
)	O
,	O
which	O
became	O
ubiquitous	O
(	O
to	O
the	O
point	O
that	O
it	O
is	O
still	O
emulated	O
as	O
the	O
baseline	O
functionality	O
of	O
most	O
modern	O
PC	O
video	O
adapter	O
chips	O
)	O
incorporates	O
a	O
compatible	O
near-superset	O
of	O
the	O
EGA	B-Device
CRTC	O
,	O
still	O
mostly-compatible	O
with	O
the	O
MC6845	B-General_Concept
(	O
but	O
by	O
this	O
point	O
without	O
the	O
light	B-Device
pen	I-Device
support	O
,	O
which	O
the	O
EGA	B-Device
CRTC	O
retained	O
)	O
.	O
</s>
<s>
The	O
MC6801	O
was	O
a	O
single-chip	O
microcomputer	O
(	O
that	O
today	O
would	O
also	O
be	O
called	O
a	O
microcontroller	B-Architecture
)	O
incorporating	O
a	O
6802	O
CPU	O
with	O
128bytes	O
of	O
RAM	B-Architecture
,	O
a	O
2KB	O
ROM	B-Device
,	O
a	O
16-bit	O
timer	O
,	O
31	O
programmable	O
parallel	O
I/O	O
lines	O
,	O
and	O
a	O
serial	O
port	O
.	O
</s>
<s>
(	O
The	O
MC6803	O
was	O
the	O
same	O
except	O
without	O
the	O
ROM	B-Device
and	O
with	O
fewer	O
different	O
bus	O
configurations	O
.	O
)	O
</s>
<s>
It	O
could	O
also	O
use	O
the	O
I/O	O
lines	O
as	O
data	O
and	O
address	O
buses	O
to	O
connect	O
to	O
standard	O
M6800	B-Device
peripherals	B-Device
.	O
</s>
<s>
This	O
35,000	O
transistor	B-Application
chip	O
was	O
too	O
expensive	O
for	O
wide-scale	O
adoption	O
in	O
automobiles	O
,	O
so	O
a	O
reduced	O
function	O
MC6805	O
single-chip	O
microcomputer	O
was	O
designed	O
.	O
</s>
<s>
The	O
Hitachi	O
HD6303	O
(	O
not	O
to	O
be	O
confused	O
with	O
the	O
Hitachi	B-General_Concept
6309	I-General_Concept
)	O
is	O
a	O
second-source	O
reimplementation	O
of	O
the	O
Motorola	O
MC6803	O
,	O
with	O
a	O
few	O
additional	O
instructions	O
,	O
and	O
a	O
slightly	O
faster	O
implementation	O
of	O
the	O
8x8	O
multiply	O
instruction	O
.	O
</s>
<s>
The	O
Hitachi	O
HD6303	O
is	O
used	O
in	O
the	O
first	O
PDA	O
,	O
the	O
1984	O
Psion	B-Application
Organiser	I-Application
.	O
</s>
<s>
The	O
Motorola	O
MC6803	O
was	O
also	O
used	O
in	O
the	O
TRS-80	B-Device
MC-10	I-Device
and	O
the	O
closely	O
related	O
Matra	B-Device
Alice	I-Device
.	O
</s>
<s>
The	O
MC6809	B-Device
was	O
the	O
most	O
advanced	O
8-bit	O
microprocessor	O
Motorola	O
produced	O
.	O
</s>
<s>
It	O
had	O
a	O
new	O
instruction	O
set	O
that	O
was	O
similar	O
to	O
the	O
6800	O
but	O
abandoned	O
op-code	B-Language
compatibility	O
for	O
improved	O
performance	O
and	O
high-level	O
language	O
support	O
;	O
the	O
6809	B-Device
and	O
6800	O
were	O
software	O
compatible	O
in	O
that	O
assemblers	B-Language
could	O
(	O
and	O
generally	O
did	O
)	O
generate	O
code	O
which	O
was	O
equivalent	O
to	O
6800	O
opcodes	B-Language
that	O
the	O
6809	B-Device
did	O
not	O
directly	O
emulate	O
.	O
</s>
<s>
In	O
that	O
sense	O
,	O
the	O
6809	B-Device
was	O
upward	O
compatible	O
with	O
the	O
6800	O
.	O
</s>
<s>
The	O
6809	B-Device
had	O
two	O
16-bit	O
index	O
registers	O
,	O
two	O
16-bit	O
stack	O
pointers	O
,	O
and	O
many	O
instructions	O
to	O
perform	O
16-bit	O
operations	O
,	O
including	O
the	O
first	O
8-bit	O
multiply	O
instruction	O
(	O
generating	O
a	O
16-bit	O
product	O
)	O
in	O
a	O
microprocessor	O
.	O
</s>
<s>
Other	O
key	O
points	O
of	O
the	O
6809	B-Device
design	O
were	O
full	O
support	O
for	O
both	O
position-independent	B-Operating_System
code	I-Operating_System
(	O
object	O
code	O
that	O
can	O
run	O
wherever	O
it	O
is	O
loaded	O
in	O
memory	O
)	O
and	O
reentrant	B-Operating_System
code	I-Operating_System
(	O
object	O
code	O
that	O
can	O
be	O
re-invoked	O
when	O
interrupted	O
or	O
by	O
calling	O
itself	O
recursively	O
)	O
,	O
features	O
previously	O
seen	O
only	O
in	O
much	O
larger	O
machines	O
such	O
as	O
IBM	B-Application
360	I-Application
mainframes	O
.	O
</s>
<s>
The	O
MITS	O
Altair	O
8800	O
,	O
the	O
first	O
successful	O
personal	O
computer	O
,	O
used	O
the	O
Intel	B-General_Concept
8080	I-General_Concept
microprocessor	O
and	O
was	O
featured	O
on	O
the	O
January	O
1975	O
cover	O
of	O
Popular	O
Electronics	O
.	O
</s>
<s>
The	O
first	O
personal	O
computers	O
using	O
the	O
Motorola	B-Device
6800	I-Device
were	O
introduced	O
in	O
late	O
1975	O
.	O
</s>
<s>
Sphere	B-Device
Corporation	I-Device
of	O
Bountiful	O
,	O
Utah	O
ran	O
a	O
quarter-page	O
advertisement	O
in	O
the	O
July	O
1975	O
issue	O
of	O
Radio-Electronics	O
for	O
a	O
computer	O
kit	O
with	O
a	O
6800	O
microprocessor	O
,	O
of	O
RAM	B-Architecture
,	O
a	O
video	O
board	O
and	O
a	O
keyboard	O
.	O
</s>
<s>
This	O
would	O
display	O
16	O
lines	O
of	O
32	O
characters	O
on	O
a	O
TV	O
or	O
monitor	B-Application
.	O
</s>
<s>
The	O
Sphere	B-Device
computer	I-Device
kits	O
began	O
shipping	O
in	O
November	O
1975	O
.	O
</s>
<s>
Southwest	O
Technical	O
Products	O
Corporation	O
of	O
San	O
Antonio	O
,	O
Texas	O
,	O
officially	O
announced	O
their	O
SWTPC	B-Device
6800	I-Device
Computer	O
System	O
in	O
November	O
1975	O
.	O
</s>
<s>
The	O
SWTPC	B-Device
6800	I-Device
was	O
based	O
on	O
the	O
Motorola	O
MEK6800	O
design	O
evaluation	O
kit	O
chip	O
set	O
and	O
used	O
the	O
MIKBUG	B-Device
ROM	B-Device
Software	O
.	O
</s>
<s>
Other	O
companies	O
,	O
for	O
instance	O
,	O
Smoke	O
Signal	O
Broadcasting	O
(	O
California	O
)	O
,	O
Gimix	O
(	O
Chicago	O
)	O
,	O
Midwest	O
Scientific	O
(	O
Olathe	O
,	O
Kansas	O
)	O
,	O
and	O
Helix	O
Systems	O
(	O
Hazelwood	O
,	O
Missouri	O
)	O
,	O
started	O
producing	O
SWTPC	B-Device
6800	I-Device
bus	O
compatible	O
boards	O
and	O
complete	O
systems	O
.	O
</s>
<s>
Technical	O
Systems	O
Consultants	O
of	O
West	O
Lafayette	O
,	O
Indiana	O
,	O
supplied	O
tape	O
based	O
software	O
for	O
the	O
6800	O
(	O
and	O
later	O
6809	B-Device
)	O
based	O
computers	O
and	O
,	O
after	O
disk	O
systems	O
became	O
available	O
,	O
operating	O
systems	O
and	O
disk	O
software	O
as	O
well	O
.	O
</s>
<s>
The	O
8080	B-General_Concept
systems	O
were	O
far	O
more	O
popular	O
than	O
the	O
6800	O
ones	O
.	O
</s>
<s>
This	O
was	O
a	O
professional	O
desktop	B-Device
computer	I-Device
that	O
had	O
a	O
6800	O
microprocessor	O
with	O
up	O
to	O
32KB	O
of	O
user	O
RAM	B-Architecture
,	O
300KB	O
magnetic	O
tape	O
storage	O
,	O
BASIC	O
in	O
ROM	B-Device
and	O
a	O
1024	O
by	O
780	O
graphics	O
display	O
.	O
</s>
<s>
The	O
6800	O
processor	O
was	O
also	O
used	O
in	O
the	O
APF	B-Device
MP1000	I-Device
game	O
console	O
.	O
</s>
<s>
The	O
Matsushita	B-Device
JR	I-Device
series	I-Device
used	O
a	O
Panasonic	O
MN1800A	O
NMOS	B-Algorithm
microprocessor	O
,	O
compatible	O
with	O
the	O
MC6802	B-Device
.	O
</s>
<s>
It	O
was	O
fitted	O
with	O
16k	O
of	O
ROM	B-Device
and	O
2k	O
of	O
RAM	B-Architecture
with	O
optional	O
IO	O
expansion	O
and	O
RAM	B-Architecture
expansion	O
to	O
4k	O
.	O
</s>
<s>
Motorola	O
's	O
next	O
generation	O
8-bit	O
microprocessor	O
architecture	O
,	O
the	O
MC6809	B-Device
(	O
1979	O
)	O
,	O
was	O
not	O
binary	O
code	O
compatible	O
with	O
the	O
6800	O
,	O
but	O
nearly	O
all	O
assembly	B-Language
code	I-Language
would	O
assemble	O
and	O
run	O
on	O
the	O
6809	B-Device
;	O
6800	O
family	O
peripheral	O
chips	O
worked	O
as	O
a	O
matter	O
of	O
course	O
.	O
</s>
<s>
The	O
following	O
6800	O
assembly	B-Language
language	I-Language
source	O
code	O
is	O
for	O
a	O
subroutine	O
named	O
memcpy	O
that	O
copies	O
a	O
block	O
of	O
data	O
bytes	O
of	O
a	O
given	O
size	O
from	O
one	O
location	O
to	O
another	O
.	O
</s>
<s>
Initially	O
Motorola	O
selected	O
American	O
Microsystems	O
Inc	O
(	O
AMI	O
)	O
as	O
a	O
second	O
source	O
for	O
the	O
M6800	B-Device
family	I-Device
.	O
</s>
<s>
Rochester	O
Electronics	O
was	O
authorized	O
by	O
Freescale/Motorola	O
in	O
2014	O
to	O
continue	O
manufacturing	O
any	O
of	O
the	O
8-bit	O
peripherals	B-Device
and	O
8-bit	O
processors	O
of	O
this	O
era	O
.	O
</s>
<s>
At	O
the	O
end	O
of	O
2016	O
,	O
Rochester	O
was	O
fully	O
qualified	O
and	O
shipping	O
the	O
MC6802	B-Device
processor	O
,	O
the	O
MC6840	O
PTM	O
,	O
and	O
the	O
MC6809	B-Device
processor	O
(	O
including	O
the	O
MC68A09	O
,	O
and	O
MC68B09	O
versions	O
)	O
and	O
can	O
still	O
be	O
bought	O
today	O
.	O
</s>
<s>
Thomas	O
H	B-Device
.	O
Bennett	O
,	O
John	O
Ekiss	O
,	O
William	O
(	O
Bill	O
)	O
Lattin	O
,	O
Jeff	O
Lavell	O
.	O
</s>
