<s>
The	O
Olivetti	B-Device
M20	I-Device
is	O
a	O
Zilog	B-Device
Z8000	I-Device
based	O
computer	O
designed	O
and	O
released	O
by	O
Olivetti	O
in	O
1982	O
.	O
</s>
<s>
Although	O
it	O
offered	O
good	O
performance	O
,	O
it	O
suffered	O
from	O
a	O
lack	O
of	O
software	O
due	O
to	O
its	O
use	O
of	O
the	O
Z8000	B-Device
processor	O
and	O
custom	O
operating	B-General_Concept
system	I-General_Concept
,	O
PCOS	O
.	O
</s>
<s>
The	O
company	O
introduced	O
the	O
IBM	B-Device
PC	I-Device
compatible	O
Olivetti	B-Operating_System
M24	I-Operating_System
in	O
1983	O
and	O
the	O
M20	O
line	O
was	O
phased	O
out	O
.	O
</s>
<s>
When	O
announced	O
on	O
March	O
31	O
,	O
1982	O
,	O
it	O
was	O
probably	O
the	O
first	O
16-bit	O
personal	B-Device
computer	I-Device
in	O
Europe	O
with	O
an	O
expected	O
price	O
range	O
of	O
US$	O
3,000	O
-6	O
,	O
000	O
.	O
</s>
<s>
InfoWorld	O
magazine	O
saw	O
the	O
M20	O
as	O
an	O
"	O
answer	O
to	O
Tandy	O
's	O
Model	O
16	O
,	O
the	O
IBM	B-Device
Personal	I-Device
Computer	I-Device
and	O
the	O
Apple	B-Device
III	I-Device
"	O
;	O
Olivetti	O
itself	O
compared	O
its	O
computer	O
to	O
the	O
IBM	B-Device
PC	I-Device
,	O
Sirius	O
Victor	O
,	O
Commodore	B-Device
8000	I-Device
and	O
Apple	B-Device
II	I-Device
in	O
television	O
advertising	O
.	O
</s>
<s>
Although	O
the	O
computer	O
was	O
initially	O
well	O
received	O
,	O
its	O
use	O
of	O
a	O
non-standard	O
OS	O
(	O
Olivetti	O
's	O
proprietary	O
PCOS	O
)	O
and	O
CPU	O
(	O
Zilog	B-Device
Z8001	I-Device
)	O
proved	O
to	O
be	O
its	O
most	O
serious	O
limitations	O
.	O
</s>
<s>
There	O
was	O
also	O
Microsoft	B-Language
BASIC	I-Language
5.2	O
with	O
full	O
support	O
for	O
the	O
hardware	O
's	O
features	O
.	O
</s>
<s>
To	O
alleviate	O
a	O
lack	O
of	O
applications	O
,	O
Olivetti	O
sold	O
a	O
CP/M	B-Application
emulator	O
for	O
US$300	O
and	O
distributed	O
certain	O
CP/M	B-Application
software	O
packages	O
(	O
dBase	B-Application
II	I-Application
and	O
SuperCalc	B-Application
)	O
for	O
their	O
computer	O
.	O
</s>
<s>
Olivetti	O
later	O
introduced	O
the	O
"	O
Alternate	O
Processor	O
Board	O
"	O
(	O
APB	O
1086	O
)	O
,	O
based	O
on	O
an	O
8MHz	O
Intel	B-General_Concept
8086	I-General_Concept
CPU	O
for	O
compatibility	O
with	O
MS-DOS	B-Application
and	O
CP/M	B-Operating_System
-86	I-Operating_System
software	O
.	O
</s>
<s>
In	O
January	O
1984	O
,	O
Olivetti	O
introduced	O
a	O
new	O
IBM	O
PC-compatible	O
computer	O
,	O
the	O
Olivetti	B-Operating_System
M24	I-Operating_System
,	O
running	O
MS-DOS	B-Application
as	O
a	O
"	O
complement	O
"	O
to	O
the	O
Olivetti	B-Device
M20	I-Device
.	O
</s>
<s>
M20	O
uses	O
Zilog	B-Device
Z8001	I-Device
4MHz	O
CPU	O
and	O
128	O
KB	O
RAM	O
,	O
which	O
can	O
be	O
expanded	O
up	O
to	O
512	O
KB	O
by	O
three	O
128	O
KB	O
memory	O
boards	O
.	O
</s>
<s>
The	O
computer	O
has	O
also	O
parallel	B-Device
(	O
IEEE-488	O
)	O
and	O
serial	B-Protocol
port	I-Protocol
(	O
RS-232-C	O
)	O
.	O
</s>
<s>
Standard	O
configuration	O
includes	O
two	O
5-inch	O
320	O
KB	O
floppy	B-Device
disk	I-Device
drives	I-Device
(	O
286	O
KB	O
formatted	O
capacity	O
)	O
.	O
</s>
<s>
Optional	O
were	O
160	O
KB	O
or	O
640	O
KB	O
(	O
compatible	O
with	O
320	O
KB	O
disks	O
)	O
drives	O
or	O
5-inch	O
hard	B-Device
disk	I-Device
in	O
place	O
of	O
one	O
of	O
the	O
floppy	B-Device
disk	I-Device
drives	I-Device
(	O
9.2	O
MB	O
formatted	O
capacity	O
)	O
.	O
</s>
<s>
Motherboard	O
has	O
two	O
expansion	O
slots	O
intended	O
for	O
the	O
hard	B-General_Concept
disk	I-General_Concept
controller	I-General_Concept
board	O
,	O
additional	O
parallel	B-Device
interface	I-Device
,	O
twin	O
serial	B-Protocol
interface	I-Protocol
or	O
Corvus	O
Omninet	O
LAN	B-General_Concept
card	O
.	O
</s>
<s>
M20	O
provides	O
512	O
×	O
256	O
display	B-General_Concept
resolution	I-General_Concept
on	O
12-inch	O
monochrome	B-Device
or	O
color	O
monitor	O
.	O
</s>
<s>
When	O
using	O
only	O
one	O
additional	O
memory	O
board	O
,	O
only	O
4	O
colors	O
form	O
8	O
color	B-Data_Structure
palette	I-Data_Structure
are	O
available	O
.	O
</s>
<s>
All	O
graphics	O
is	O
pixel-generated	O
(	O
there	O
is	O
no	O
specific	O
text	B-Application
mode	I-Application
)	O
,	O
text	O
characters	O
use	O
resolution	O
64	O
characters	O
per	O
16	O
rows	O
(	O
or	O
80	O
characters	O
per	O
25	O
rows	O
)	O
.	O
</s>
<s>
Instead	O
of	O
standard	O
function	B-Application
keys	I-Application
,	O
user	O
defined	O
special	O
functions	O
are	O
invoked	O
by	O
pressing	O
orange-colored	O
or	O
light-blue-colored	O
key	O
along	O
with	O
another	O
key	O
(	O
creates	O
24	O
user-definable	O
function	B-Application
keys	I-Application
)	O
.	O
</s>
<s>
Numeric	B-Device
keypad	I-Device
serves	O
also	O
as	O
cursor	B-Application
controls	I-Application
.	O
</s>
<s>
PCOS	O
(	O
Professional	O
Computer	B-General_Concept
Operating	I-General_Concept
System	I-General_Concept
)	O
is	O
a	O
single-user	O
,	O
single-tasking	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
It	O
was	O
used	O
on	O
the	O
Olivetti	B-Device
M20	I-Device
and	O
L1	O
computers	O
.	O
</s>
<s>
Operating	B-General_Concept
system	I-General_Concept
with	O
BASIC	O
interpreter	O
takes	O
64	O
KB	O
RAM	O
,	O
another	O
16	O
KB	O
are	O
reserved	O
for	O
screen	O
output	O
and	O
user	O
is	O
left	O
with	O
only	O
around	O
40	O
KB	O
RAM	O
on	O
unexpanded	O
machine	O
.	O
</s>
<s>
Version	O
2.0	O
supports	O
dynamic	B-General_Concept
memory	I-General_Concept
allocation	I-General_Concept
alleviating	O
segmented	B-General_Concept
memory	I-General_Concept
limitations	O
of	O
the	O
Z8000	B-Device
CPU	O
.	O
</s>
<s>
Standard	O
OS	O
configuration	O
includes	O
BASIC	O
interpreter	O
,	O
other	O
programming	O
languages	O
(	O
Assembler	B-Language
and	O
PASCAL	B-Application
)	O
are	O
optional	O
.	O
</s>
