<s>
They	O
provided	O
the	O
capability	O
of	O
the	O
HP	B-Device
9800	I-Device
series	I-Device
desktop	I-Device
computers	I-Device
with	O
an	O
integrated	O
monitor	O
in	O
a	O
smaller	O
package	O
including	O
storage	O
and	O
printer	O
,	O
at	O
half	O
the	O
price	O
.	O
</s>
<s>
BYTE	B-Application
wrote	O
"	O
we	O
were	O
impressed	O
with	O
the	O
performance	O
...	O
the	O
graphics	O
alone	O
make	O
this	O
an	O
attractive	O
,	O
albeit	O
not	O
inexpensive	O
,	O
alternate	O
to	O
existing	O
small	O
systems	O
on	O
the	O
market	O
...	O
it	O
is	O
our	O
guess	O
that	O
many	O
personal	O
computer	O
experimenters	O
and	O
hackers	O
will	O
want	O
this	O
machine.	O
"	O
</s>
<s>
In	O
a	O
typewriter-style	O
desktop	O
case	O
,	O
the	O
HP-85	O
contains	O
the	O
CPU	B-Device
and	O
keyboard	O
,	O
with	O
a	O
ROM-based	O
operating	O
system	O
(	O
like	O
the	O
9800	O
series	O
)	O
,	O
16	O
KB	O
dynamic	B-Architecture
RAM	I-Architecture
,	O
a	O
5-inch	O
CRT	B-Device
screen	I-Device
(	O
16	O
lines	O
of	O
32	O
characters	O
,	O
or	O
256×192	O
pixels	B-Algorithm
)	O
,	O
a	O
tape	O
drive	O
for	O
DC-100	B-Operating_System
cartridges	O
(	O
capacity	O
,	O
transfer	O
)	O
,	O
and	O
a	O
thermal	O
printer	O
.	O
</s>
<s>
The	O
chassis	O
includes	O
four	O
module	O
slots	O
in	O
the	O
back	O
for	O
expansion	O
which	O
can	O
hold	O
memory	O
modules	O
,	O
ROM	B-Device
extensions	O
,	O
or	O
interfaces	O
such	O
as	O
RS-232	O
and	O
GPIB	O
.	O
</s>
<s>
The	O
machines	O
were	O
built	O
around	O
an	O
HP-proprietary	O
CPU	B-Device
code-named	O
Capricorn	B-Device
running	O
at	O
and	O
had	O
a	O
BASIC	B-Language
interpreter	O
in	O
ROM	B-Device
(	O
)	O
.	O
</s>
<s>
Programs	O
could	O
be	O
stored	O
on	O
DC-100	B-Operating_System
cartridge	O
tapes	O
or	O
on	O
external	O
disk/tape	O
units	O
.	O
</s>
<s>
The	O
standard	O
number	O
representation	O
was	O
a	O
floating	B-Algorithm
point	I-Algorithm
format	I-Algorithm
with	O
a	O
12-digit	O
(	O
decimal	O
)	O
mantissa	B-Algorithm
and	O
exponents	O
up	O
to	O
±499	O
.	O
</s>
<s>
The	O
language	O
supported	O
two-dimensional	O
arrays	O
,	O
and	O
a	O
ROM	B-Device
extension	O
made	O
high-level	O
functions	O
such	O
as	O
matrix	O
multiplication	O
and	O
inversion	O
available	O
.	O
</s>
<s>
For	O
the	O
larger	O
HP-86	O
and	O
HP-87	O
series	O
,	O
HP	O
also	O
offered	O
a	O
plug-in	O
CP/M	B-Application
processor	O
card	O
with	O
a	O
separate	O
Zilog	B-General_Concept
Z80	I-General_Concept
processor	O
.	O
</s>
<s>
The	O
late	O
1970s	O
saw	O
the	O
development	O
of	O
inexpensive	O
home	O
computers	O
such	O
as	O
the	O
Apple	O
and	O
TRS-80	B-Device
.	O
</s>
<s>
Steve	O
Wozniak	O
had	O
developed	O
the	O
Apple	O
computer	O
with	O
the	O
idea	O
of	O
a	O
computer	O
that	O
worked	O
in	O
BASIC	B-Language
when	O
it	O
was	O
turned	O
on	O
,	O
and	O
offered	O
HP	O
rights	O
to	O
the	O
Apple	O
computer	O
.	O
</s>
<s>
In	O
an	O
interview	O
he	O
did	O
note	O
that	O
soon	O
after	O
that	O
,	O
the	O
calculator	O
division	O
was	O
starting	O
an	O
8-bit	O
computer	O
project	O
called	O
Capricorn	B-Device
,	O
and	O
he	O
was	O
n't	O
allowed	O
to	O
work	O
on	O
that	O
project	O
.	O
</s>
<s>
Ultimately	O
,	O
the	O
market	O
for	O
desktop	O
computing	O
would	O
go	O
to	O
IBM	B-Device
PC	I-Device
compatible	O
personal	O
computers	O
with	O
a	O
floppy	O
disk	O
drive	O
based	O
operating	O
system	O
,	O
and	O
an	O
industry	O
standard	O
Intel	O
8088	O
processor	O
(	O
the	O
IBM	B-Device
PC	I-Device
was	O
announced	O
shortly	O
after	O
the	O
80	O
series	O
)	O
.	O
</s>
<s>
Model	O
Year	O
Price	O
Remarks	O
HP-85A	O
1980	O
$	O
3,250	O
(	O
see	O
Inflation	O
Conversion	O
Factors	O
for	O
Dollars	O
)	O
16	O
K	O
RAM	B-Architecture
,	O
32	O
K	O
ROM	B-Device
;	O
5	O
"	O
CRT	B-Device
,	O
32×16	O
text	O
or	O
256×192	O
graphics	O
;	O
tape	O
drive	O
,	O
printerHP-83	O
1981	O
$	O
2,250	O
(	O
ibid	O
.	O
)	O
</s>
<s>
update	O
to	O
HP-85A	O
;	O
64	O
K	O
RAM	B-Architecture
(	O
32	O
K	O
program/variables	O
,	O
32	O
K	O
RAM	B-Application
disk	I-Application
;	O
I/O	O
,	O
EDISK	O
,	O
and	O
Mass	O
Storage	O
ROM	B-Device
built	O
inHP-86B	O
1983	O
$	O
1,595	O
update	O
to	O
HP-86	O
;	O
built-in	O
HPIB	O
instead	O
of	O
diskette	O
and	O
Centronics	B-Device
ports	I-Device
;	O
128	O
K	O
RAM	B-Architecture
;	O
EDISK	O
ROM	B-Device
built-inHP-87XM	O
1983	O
$	O
2,995	O
(	O
ibid	O
.	O
)	O
</s>
<s>
83/85	O
86/87	O
Function	O
Description	O
ID	O
"	O
ID	O
"	O
refers	O
to	O
the	O
internal	O
ROM	B-Device
identification	O
,	O
i.e.	O
</s>
<s>
the	O
base	O
address	O
,	O
which	O
needs	O
to	O
be	O
unique	O
in	O
the	O
system.00085-15003	O
00087-15003	O
I/O	O
Access	O
GPIB	O
,	O
serial	O
and	O
parallel	O
(	O
GPIO	O
)	O
interfaces	O
19200085-15001	O
built-in	O
Mass	O
storage	O
Access	O
"	O
Amigo	B-Device
"	O
compatible	O
diskette/disk	O
drives	O
on	O
GPIB	O
.	O
</s>
<s>
20800085-15002	O
00087-15002	O
Printer	O
/	O
plotter	O
Support	O
for	O
external	O
printer/plotter	O
(	O
on	O
86/87	O
needed	O
for	O
plotter	O
only	O
)	O
24000085-15005	O
00087-15005	O
Advanced	O
programming	O
Extended	O
Basic	B-Language
commands	O
232,231	O
00087-15012	O
Electronic	O
disk	O
Use	O
part	O
of	O
RAM	B-Application
as	I-Application
a	I-Application
disk	I-Application
drive	I-Application
,	O
built	O
into	O
85B	O
,	O
86B	O
.	O
</s>
<s>
82936A	O
ROM	B-Device
drawer	O
for	O
up	O
to	O
six	O
of	O
the	O
above	O
ROMs	O
(	O
max	O
one	O
per	O
unit	O
)	O
82903A	O
16	O
K	O
memory	O
module	O
,	O
for	O
HP-85A	O
only	O
(	O
max	O
one	O
per	O
unit	O
)	O
Note	O
:	O
*	O
Do	O
not	O
use	O
with	O
HP-85B	O
,	O
may	O
cause	O
damage*82908A	O
64	O
K	O
memory	O
module	O
,	O
for	O
HP-85B	O
or	O
HP-86/8782909A	O
128	O
K	O
memory	O
module	O
,	O
for	O
HP-85B	O
or	O
HP-86/8782900A	O
CP/M	B-Application
System	O
(	O
for	O
HP-86/87	O
only	O
)	O
.	O
</s>
<s>
Contains	O
a	O
Zilog	B-General_Concept
Z80	I-General_Concept
microprocessor	O
and	O
64	O
kilobytes	O
dedicated	O
RAM.82928A	O
System	O
monitor	O
for	O
assembly	O
development	O
.	O
</s>
<s>
The	O
interface	O
modules	O
for	O
the	O
series	O
80	O
were	O
built	O
around	O
a	O
proprietary	O
bus	O
interface	O
chip	O
connecting	O
a	O
standard	O
Intel	B-Device
8049	I-Device
microcontroller	I-Device
to	O
the	O
main	O
bus	O
.	O
</s>
<s>
Interface	O
functions	O
such	O
as	O
handshaking	O
were	O
offloaded	O
to	O
the	O
8049	B-Device
firmware	B-Application
.	O
</s>
