<s>
The	O
IBM	B-Device
5100	I-Device
Portable	B-Device
Computer	I-Device
is	O
one	O
of	O
the	O
first	O
portable	B-Device
computers	I-Device
,	O
introduced	O
in	O
September	O
1975	O
,	O
six	O
years	O
before	O
the	O
IBM	B-Device
Personal	I-Device
Computer	I-Device
,	O
and	O
eight	O
before	O
the	O
first	O
successful	O
IBM	O
compatible	O
portable	B-Device
computer	I-Device
,	O
the	O
Compaq	B-Device
Portable	I-Device
.	O
</s>
<s>
It	O
was	O
the	O
evolution	O
of	O
a	O
prototype	O
called	O
the	O
SCAMP	O
(	O
Special	O
Computer	O
APL	B-Language
Machine	O
Portable	O
)	O
that	O
was	O
developed	O
at	O
the	O
IBM	O
Palo	O
Alto	O
Scientific	O
Center	O
in	O
1973	O
.	O
</s>
<s>
When	O
the	O
IBM	B-Device
PC	I-Device
was	O
introduced	O
in	O
1981	O
,	O
it	O
was	O
originally	O
designated	O
as	O
the	O
IBM	B-Device
5150	I-Device
,	O
putting	O
it	O
in	O
the	O
"	O
5100	O
"	O
series	O
,	O
though	O
its	O
architecture	O
was	O
unrelated	O
to	O
the	O
IBM	B-Device
5100	I-Device
's	O
.	O
</s>
<s>
Previously	O
,	O
a	O
truck-based	O
IBM	B-Device
1401	I-Device
configured	O
in	O
1960	O
for	O
military	O
use	O
was	O
designated	O
a	O
portable	B-Device
computer	I-Device
,	O
and	O
nicknamed	O
a	O
DataMobile	O
.	O
</s>
<s>
The	O
IBM	B-Device
5100	I-Device
was	O
withdrawn	O
in	O
March	O
1982	O
,	O
by	O
which	O
time	O
IBM	O
had	O
announced	O
its	O
larger	O
cousins	O
,	O
the	O
IBM	B-Device
5110	I-Device
(	O
January	O
1978	O
)	O
and	O
the	O
IBM	B-Device
5120	I-Device
(	O
February	O
1980	O
)	O
.	O
</s>
<s>
In	O
1973	O
,	O
Bill	O
Lowe	O
was	O
instrumental	O
in	O
fostering	O
an	O
engineering	O
prototype	O
called	O
SCAMP	O
(	O
Special	O
Computer	O
APL	B-Language
Machine	O
Portable	O
)	O
created	O
by	O
Dr.	O
Paul	O
Friedl	O
and	O
a	O
team	O
at	O
the	O
IBM	O
Los	O
Gatos	O
Scientific	O
Center	O
.	O
</s>
<s>
SCAMP	O
emulated	B-Application
an	O
IBM	B-Device
1130	I-Device
minicomputer	O
in	O
order	O
to	O
run	O
APL	B-Language
\1130	O
.	O
</s>
<s>
In	O
1973	O
,	O
APL	B-Language
was	O
generally	O
available	O
only	O
on	O
mainframe	O
computers	O
,	O
and	O
most	O
desktop	O
sized	O
microcomputers	O
such	O
as	O
the	O
Wang	B-Language
2200	I-Language
or	O
HP	B-Device
9800	I-Device
offered	O
only	O
BASIC	B-Language
.	O
</s>
<s>
Because	O
SCAMP	O
was	O
the	O
first	O
to	O
emulate	O
APL	B-Language
\1130	O
performance	O
on	O
a	O
portable	O
,	O
single	O
user	O
computer	O
,	O
PC	O
Magazine	O
in	O
1983	O
designated	O
SCAMP	O
a	O
"	O
revolutionary	O
concept	O
"	O
and	O
"	O
the	O
world	O
's	O
first	O
personal	O
computer	O
"	O
.	O
</s>
<s>
The	O
IBM	B-Device
5100	I-Device
is	O
based	O
on	O
a	O
16-bit	O
processor	B-Device
module	O
called	O
PALM	B-Device
(	O
Program	O
All	O
Logic	O
in	O
Microcode	B-Device
)	O
.	O
</s>
<s>
The	O
IBM	B-Device
5100	I-Device
Maintenance	O
Information	O
Manual	O
also	O
referred	O
to	O
the	O
PALM	B-Device
module	O
as	O
the	O
controller	O
.	O
</s>
<s>
The	O
PALM	B-Device
could	O
directly	O
address	O
of	O
memory	O
.	O
</s>
<s>
Some	O
configurations	O
of	O
the	O
IBM	B-Device
5100	I-Device
had	O
Executable	O
ROS	O
(	O
ROM	B-Device
)	O
and	O
RAM	B-Architecture
memory	I-Architecture
totalling	O
more	O
than	O
,	O
so	O
a	O
simple	O
bank	B-General_Concept
switching	I-General_Concept
scheme	O
was	O
used	O
.	O
</s>
<s>
The	O
actual	O
APL	B-Language
and	O
BASIC	B-Language
interpreters	O
were	O
stored	O
in	O
a	O
separate	O
Language	O
ROS	O
address	O
space	O
which	O
the	O
PALM	B-Device
treats	O
as	O
a	O
peripheral	O
device	O
.	O
</s>
<s>
There	O
were	O
twelve	O
models	O
available	O
:	O
with	O
BASIC	B-Language
,	O
APL	B-Language
,	O
or	O
both	O
.	O
</s>
<s>
In	O
December	O
1975	O
BYTE	B-Application
stated	O
"	O
Welcome	O
,	O
IBM	O
,	O
to	O
personal	O
computing	O
"	O
.	O
</s>
<s>
A	O
single	O
integrated	O
unit	O
provided	O
the	O
keyboard	B-Device
,	O
five-inch	O
CRT	B-Device
display	I-Device
,	O
tape	O
drive	O
,	O
processor	B-Device
,	O
several	O
hundred	O
KB	O
of	O
read-only	B-Device
memory	I-Device
containing	O
system	B-Application
software	I-Application
,	O
and	O
up	O
to	O
of	O
RAM	B-Architecture
.	O
</s>
<s>
In	O
1975	O
,	O
it	O
was	O
an	O
amazing	O
technical	O
accomplishment	O
to	O
package	O
a	O
complete	O
computer	O
with	O
a	O
large	O
amount	O
of	O
ROM	B-Device
and	O
RAM	B-Architecture
,	O
CRT	B-Device
display	I-Device
,	O
and	O
a	O
tape	O
drive	O
into	O
a	O
machine	O
that	O
small	O
.	O
</s>
<s>
Earlier	O
desktop	O
computers	O
of	O
approximately	O
the	O
same	O
size	O
,	O
such	O
as	O
the	O
HP	B-Device
9830	I-Device
,	O
did	O
not	O
include	O
a	O
CRT	B-Device
nor	O
nearly	O
as	O
much	O
memory	O
.	O
</s>
<s>
The	O
5100	O
has	O
an	O
internal	O
CRT	B-Device
(	O
five-inch	O
diagonal	O
)	O
and	O
displays	O
16	O
lines	O
of	O
64	O
characters	O
.	O
</s>
<s>
Also	O
there	O
was	O
a	O
switch	O
to	O
display	O
the	O
first	O
512	O
bytes	B-Application
of	O
main	O
memory	O
in	O
hexadecimal	O
for	O
diagnostic	O
purposes	O
.	O
</s>
<s>
Mass	O
storage	O
was	O
provided	O
by	O
removable	O
quarter-inch	B-Device
cartridge	I-Device
(	O
QIC	O
)	O
magnetic	O
tape	O
drives	O
that	O
use	O
standard	O
DC300	B-Device
cartridges	O
to	O
store	O
.	O
</s>
<s>
The	O
data	O
format	O
included	O
several	O
types	O
and	O
were	O
written	O
in	O
512	O
byte	B-Application
records	O
.	O
</s>
<s>
The	O
introduction	O
of	O
a	O
floppy	O
option	O
was	O
not	O
until	O
the	O
IBM	B-Device
5110	I-Device
.	O
</s>
<s>
At	O
the	O
same	O
time	O
IBM	O
announced	O
the	O
IBM	B-Device
5100	I-Device
,	O
it	O
also	O
announced	O
the	O
IBM	B-Device
5100	I-Device
Communications	O
Adapter	O
,	O
that	O
allowed	O
the	O
5100	O
to	O
transmit	O
data	O
to	O
and	O
receive	O
data	O
from	O
a	O
remote	O
system	O
.	O
</s>
<s>
It	O
made	O
the	O
5100	O
appear	O
the	O
same	O
as	O
an	O
IBM	O
2741	O
Communications	O
Terminal	B-General_Concept
and	O
was	O
designed	O
to	O
be	O
able	O
to	O
communicate	O
with	O
IBM	O
2741	O
compatible	O
machines	O
in	O
start-stop	O
mode	O
using	O
the	O
EBCD	B-Language
(	O
Extended	O
Binary	O
Coded	O
Decimal	O
)	O
notation	O
.	O
</s>
<s>
EBCD	B-Language
was	O
similar	O
to	O
the	O
more	O
common	O
IBM	O
EBCDIC	B-Language
code	O
,	O
but	O
not	O
identical	O
.	O
</s>
<s>
In	O
order	O
to	O
access	O
the	O
port	O
extensions	O
,	O
they	O
needed	O
to	O
be	O
loaded	O
from	O
tape	O
for	O
the	O
APL	B-Language
and	O
BASIC	B-Language
programming	I-Language
languages	I-Language
.	O
</s>
<s>
Unlike	O
the	O
Communications	O
Adapter	O
which	O
could	O
only	O
be	O
used	O
to	O
connect	O
devices	O
that	O
supported	O
the	O
IBM	O
2741	O
Communications	O
Terminal	B-General_Concept
,	O
this	O
feature	O
allowed	O
users	O
to	O
connect	O
and	O
code	O
for	O
any	O
device	O
that	O
used	O
a	O
standard	O
Serial	O
I/O	O
port	O
,	O
including	O
devices	O
not	O
made	O
by	O
IBM	O
.	O
</s>
<s>
An	O
external	O
video	O
monitor	O
receiver	O
could	O
be	O
connected	O
to	O
the	O
IBM	B-Device
5100	I-Device
via	O
a	O
BNC	B-Protocol
connector	I-Protocol
on	O
the	O
back	O
panel	O
.	O
</s>
<s>
In	O
Volume	O
16	O
,	O
Number	O
1	O
,	O
Page	O
41	O
(	O
1977	O
)	O
of	O
the	O
IBM	O
Systems	O
Journal	O
the	O
article	O
"	O
The	O
IBM	B-Device
5100	I-Device
and	O
the	O
Research	O
Device	O
Coupler	O
—	O
A	O
personal	O
laboratory	O
automation	O
system	O
"	O
read	O
:	O
"	O
A	O
small	O
laboratory	O
automation	O
system	O
has	O
been	O
developed	O
by	O
using	O
the	O
IBM	B-Device
5100	I-Device
Portable	B-Device
Computer	I-Device
in	O
conjunction	O
with	O
the	O
Research	O
Device	O
Coupler	O
.	O
</s>
<s>
This	O
compact	O
system	O
provides	O
a	O
dedicated	O
,	O
high-level-language	O
computer	O
and	O
a	O
versatile	O
data	B-Algorithm
acquisition	I-Algorithm
and	O
control	O
interface	O
for	O
experiments	O
in	O
which	O
data	O
rates	O
do	O
not	O
exceed	O
9600	O
baud	O
.	O
</s>
<s>
The	O
5100	O
was	O
available	O
with	O
APL	B-Language
,	O
BASIC	B-Language
,	O
or	O
both	O
programming	O
languages	O
.	O
</s>
<s>
At	O
the	O
time	O
of	O
introduction	O
,	O
APL	B-Language
was	O
generally	O
available	O
only	O
on	O
mainframe	O
computers	O
,	O
and	O
most	O
desktop	O
sized	O
computers	O
such	O
as	O
the	O
Wang	B-Language
2200	I-Language
or	O
HP	B-Device
9830	I-Device
offered	O
only	O
BASIC	B-Language
.	O
</s>
<s>
As	O
a	O
desktop	O
computer	O
offering	O
APL	B-Language
,	O
the	O
5100	O
competed	O
with	O
,	O
and	O
indeed	O
may	O
have	O
been	O
inspired	O
by	O
,	O
the	O
earlier	O
MCM/70	B-Device
.	O
</s>
<s>
On	O
the	O
5100	O
's	O
front	O
panel	O
,	O
it	O
was	O
the	O
third	O
toggle	O
from	O
the	O
left	O
:	O
up	O
for	O
APL	B-Language
,	O
down	O
for	O
BASIC	B-Language
.	O
</s>
<s>
When	O
the	O
engineers	O
at	O
IBM	O
asked	O
one	O
beta	O
tester	O
,	O
Donald	O
Polonis	O
,	O
for	O
his	O
analysis	O
,	O
he	O
commented	O
that	O
if	O
folks	O
had	O
to	O
learn	O
APL	B-Language
to	O
use	O
it	O
,	O
the	O
IBM	B-Device
5100	I-Device
would	O
not	O
make	O
it	O
as	O
a	O
personal	O
computer	O
.	O
</s>
<s>
Presumably	O
,	O
the	O
special	O
APL	B-Language
character	O
set	O
and	O
APL	B-Language
keyboard	B-Device
were	O
the	O
primary	O
obstacles	O
to	O
newcomers	O
learning	O
APL	B-Language
easily	O
.	O
</s>
<s>
APL	B-Language
had	O
powerful	O
features	O
for	O
manipulating	O
data	O
as	O
vectors	B-Data_Structure
and	O
matrices	B-Architecture
,	O
while	O
the	O
competing	O
HP	B-Device
9830	I-Device
had	O
to	O
offer	O
language	O
extensions	O
on	O
an	O
add-on	O
ROM	B-Device
for	O
matrix	O
operations	O
.	O
</s>
<s>
Although	O
not	O
meant	O
for	O
regular	O
users	O
,	O
the	O
maintenance	O
manual	O
described	O
a	O
keyboard	B-Device
sequence	O
to	O
switch	O
the	O
5100	O
into	O
a	O
maintenance	O
mode	O
.	O
</s>
<s>
In	O
this	O
mode	O
it	O
was	O
possible	O
to	O
read	O
and	O
write	O
directly	O
in	O
RAM	B-Architecture
memory	I-Architecture
,	O
video	O
memory	O
,	O
CPU	O
registers	O
,	O
interrupt	O
vectors	B-Data_Structure
,	O
clock	O
counter	O
,	O
etc.	O
,	O
using	O
hexadecimal	O
codes	O
equivalent	O
to	O
assembly	O
language	O
.	O
</s>
<s>
This	O
allowed	O
writing	O
sophisticated	O
programs	O
directly	O
into	O
RAM	B-Architecture
.	O
</s>
<s>
The	O
5100	O
was	O
based	O
on	O
IBM	O
's	O
innovative	O
concept	O
that	O
,	O
using	O
an	O
emulator	B-Application
written	O
in	O
microcode	B-Device
,	O
a	O
small	O
and	O
relatively	O
cheap	O
computer	O
could	O
run	O
programs	O
already	O
written	O
for	O
much	O
larger	O
,	O
and	O
much	O
more	O
expensive	O
,	O
existing	O
computers	O
,	O
without	O
the	O
time	O
and	O
expense	O
of	O
writing	O
and	O
debugging	O
new	O
programs	O
.	O
</s>
<s>
Two	O
such	O
programs	O
were	O
included	O
:	O
a	O
slightly	O
modified	O
version	O
of	O
APLSV	O
,	O
IBM	O
's	O
APL	B-Language
interpreter	O
for	O
its	O
System/370	B-Device
mainframes	O
,	O
and	O
the	O
BASIC	B-Language
interpreter	O
used	O
on	O
IBM	O
's	O
System/3	B-Device
minicomputer	O
.	O
</s>
<s>
Consequently	O
,	O
the	O
5100	O
's	O
microcode	B-Device
was	O
written	O
to	O
emulate	O
most	O
of	O
the	O
functionality	O
of	O
both	O
a	O
System/370	B-Device
and	O
a	O
System/3	B-Device
.	O
</s>
<s>
IBM	O
later	O
used	O
the	O
same	O
approach	O
for	O
its	O
1983	O
introduction	O
of	O
the	O
XT/370	O
model	O
of	O
the	O
IBM	B-Device
PC	I-Device
,	O
which	O
was	O
a	O
standard	O
IBM	B-Device
PC	I-Device
XT	I-Device
with	O
the	O
addition	O
of	O
a	O
System/370	B-Device
emulator	B-Application
card	O
.	O
</s>
