<s>
The	O
VT100	B-Device
is	O
a	O
video	B-General_Concept
terminal	I-General_Concept
,	O
introduced	O
in	O
August	O
1978	O
by	O
Digital	O
Equipment	O
Corporation	O
(	O
DEC	O
)	O
.	O
</s>
<s>
It	O
was	O
one	O
of	O
the	O
first	O
terminals	O
to	O
support	O
ANSI	O
escape	O
codes	O
for	O
cursor	O
control	O
and	O
other	O
tasks	O
,	O
and	O
added	O
a	O
number	O
of	O
extended	O
codes	O
for	O
special	O
features	O
like	O
controlling	O
the	O
status	O
lights	O
on	O
the	O
keyboard	B-Device
.	O
</s>
<s>
This	O
led	O
to	O
rapid	O
uptake	O
of	O
the	O
ANSI	O
standard	O
,	O
which	O
became	O
the	O
de	O
facto	O
standard	O
for	O
hardware	O
video	B-General_Concept
terminals	I-General_Concept
and	O
later	O
terminal	B-Application
emulators	I-Application
.	O
</s>
<s>
The	O
VT100	B-Device
series	O
,	O
especially	O
the	O
VT102	O
,	O
was	O
extremely	O
successful	O
in	O
the	O
market	O
,	O
and	O
made	O
DEC	O
the	O
leading	O
terminal	B-General_Concept
vendor	O
at	O
the	O
time	O
.	O
</s>
<s>
The	O
VT100	B-Device
series	O
was	O
replaced	O
by	O
the	O
VT200	B-Device
series	I-Device
starting	O
in	O
1983	O
,	O
which	O
proved	O
equally	O
successful	O
.	O
</s>
<s>
Ultimately	O
,	O
over	O
six	O
million	O
terminals	O
in	O
the	O
VT	O
series	O
were	O
sold	O
,	O
based	O
largely	O
on	O
the	O
success	O
of	O
the	O
VT100	B-Device
.	O
</s>
<s>
DEC	O
's	O
first	O
video	B-General_Concept
terminal	I-General_Concept
was	O
the	O
VT05	B-Application
(	O
1970	O
)	O
,	O
succeeded	O
by	O
the	O
VT50	B-Application
(	O
1974	O
)	O
,	O
and	O
soon	O
upgraded	O
to	O
the	O
VT52	B-Application
(	O
1975	O
)	O
.	O
</s>
<s>
The	O
VT52	B-Application
featured	O
a	O
text	O
display	O
with	O
80	O
columns	O
and	O
24	O
rows	O
,	O
bidirectional	O
scrolling	O
,	O
and	O
a	O
custom	O
control	O
protocol	O
that	O
allowed	O
the	O
cursor	O
to	O
be	O
moved	O
about	O
the	O
screen	O
.	O
</s>
<s>
These	O
"	O
smart	O
terminals	O
"	O
were	O
a	O
hit	O
due	O
both	O
to	O
their	O
capabilities	O
and	O
to	O
their	O
ability	O
to	O
be	O
run	O
over	O
inexpensive	O
serial	O
links	O
,	O
rather	O
than	O
custom	O
proprietary	O
connections	O
as	O
in	O
the	O
case	O
of	O
systems	O
like	O
the	O
IBM	B-Operating_System
3270	I-Operating_System
,	O
which	O
generally	O
required	O
expensive	O
controllers	O
for	O
distributed	O
applications	O
.	O
</s>
<s>
In	O
contrast	O
,	O
"	O
dumb	O
terminals	O
"	O
or	O
"	O
glass	B-General_Concept
teletypes	I-General_Concept
"	O
like	O
the	O
ADM-3A	B-Device
(	O
1976	O
)	O
lacked	O
advanced	O
features	O
such	O
as	O
full	O
cursor	O
addressability	O
,	O
and	O
competed	O
mostly	O
on	O
lowest	O
possible	O
hardware	O
cost	O
.	O
</s>
<s>
The	O
VT100	B-Device
was	O
introduced	O
in	O
August	O
1978	O
,	O
replacing	O
the	O
VT50/VT52	O
family	O
.	O
</s>
<s>
Like	O
the	O
earlier	O
models	O
,	O
it	O
communicated	O
with	O
its	O
host	B-Application
system	O
over	O
serial	O
lines	O
at	O
a	O
minimum	O
speed	O
of	O
50	O
bit/s	O
,	O
but	O
increased	O
the	O
maximum	O
speed	O
to	O
19,200	O
bit/s	O
,	O
double	O
that	O
of	O
the	O
VT52	B-Application
.	O
</s>
<s>
The	O
terminal	B-General_Concept
provided	O
an	O
option	O
for	O
"	O
smooth	O
scrolling	O
"	O
,	O
whereby	O
displayed	O
lines	O
of	O
text	O
were	O
moved	O
gradually	O
up	O
or	O
down	O
the	O
screen	O
to	O
make	O
room	O
for	O
new	O
lines	O
,	O
instead	O
of	O
advancing	O
in	O
sudden	O
"	O
jumps	O
"	O
.	O
</s>
<s>
Unlike	O
the	O
VT50/52	O
'	O
s	O
proprietary	O
cursor	O
control	O
language	O
,	O
the	O
VT100	B-Device
was	O
based	O
on	O
the	O
newly	O
emerging	O
ANSI	O
X3.64	O
standard	O
for	O
command	O
codes	O
.	O
</s>
<s>
The	O
introduction	O
of	O
low-cost	O
microprocessors	B-Architecture
and	O
the	O
ever-falling	O
cost	O
of	O
computer	B-General_Concept
memory	I-General_Concept
offered	O
greatly	O
expanded	O
capabilities	O
,	O
and	O
the	O
VT100	B-Device
used	O
the	O
new	O
Intel	B-General_Concept
8080	I-General_Concept
as	O
its	O
internal	O
processor	B-Device
.	O
</s>
<s>
In	O
addition	O
,	O
the	O
VT100	B-Device
provided	O
backwards	B-General_Concept
compatibility	I-General_Concept
for	O
VT52-compatible	O
software	O
,	O
by	O
also	O
supporting	O
the	O
older	O
control	O
sequences	O
.	O
</s>
<s>
Other	O
improvements	O
beyond	O
the	O
VT52	B-Application
included	O
a	O
132-column	O
mode	O
,	O
and	O
a	O
variety	O
of	O
"	O
graphic	O
renditions	O
"	O
including	O
blinking	O
,	O
bolding	O
,	O
reverse	B-General_Concept
video	I-General_Concept
,	O
and	O
underlining	O
.	O
</s>
<s>
The	O
VT100	B-Device
also	O
introduced	O
an	O
additional	O
box-drawing	O
character	O
set	O
containing	O
various	O
pseudographics	O
that	O
allowed	O
the	O
drawing	O
of	O
on-screen	O
forms	O
.	O
</s>
<s>
All	O
configuration	O
setup	O
of	O
the	O
VT100	B-Device
was	O
accomplished	O
using	O
interactive	O
displays	O
presented	O
on	O
the	O
screen	O
;	O
the	O
setup	O
data	O
was	O
stored	O
in	O
non-volatile	B-General_Concept
memory	I-General_Concept
within	O
the	O
terminal	B-General_Concept
.	O
</s>
<s>
Maintainability	O
was	O
also	O
significantly	O
improved	O
,	O
since	O
a	O
VT100	B-Device
could	O
be	O
quickly	O
dismantled	O
into	O
replaceable	O
modules	O
.	O
</s>
<s>
In	O
1983	O
,	O
the	O
VT100	B-Device
was	O
replaced	O
by	O
the	O
more	O
powerful	O
VT200	B-Device
series	I-Device
terminals	O
such	O
as	O
the	O
VT220	B-Device
.	O
</s>
<s>
The	O
VT100	B-Device
was	O
the	O
first	O
of	O
Digital	O
's	O
terminals	O
to	O
be	O
based	O
on	O
an	O
industry-standard	O
microprocessor	B-Architecture
,	O
the	O
Intel	B-General_Concept
8080	I-General_Concept
.	O
</s>
<s>
Options	O
could	O
be	O
added	O
to	O
the	O
terminal	B-General_Concept
to	O
support	O
an	O
external	O
printer	O
,	O
additional	O
graphic	O
renditions	O
,	O
and	O
more	O
character	O
memory	O
.	O
</s>
<s>
The	O
last	O
option	O
,	O
known	O
as	O
the	O
"	O
Advanced	O
Video	O
Option	O
"	O
or	O
AVO	O
,	O
allowed	O
the	O
terminal	B-General_Concept
to	O
support	O
a	O
full	O
24	O
lines	O
of	O
text	O
in	O
132-column	O
mode	O
,	O
increasing	O
from	O
the	O
14	O
lines	O
of	O
the	O
unexpanded	O
model	O
when	O
used	O
in	O
132-column	O
mode	O
.	O
</s>
<s>
The	O
VT100	B-Device
became	O
a	O
platform	O
on	O
which	O
Digital	O
constructed	O
several	O
related	O
hardware	O
products	O
.	O
</s>
<s>
The	O
VT101	O
was	O
essentially	O
a	O
base-model	O
VT100	B-Device
,	O
while	O
the	O
VT102	O
came	O
standard	O
with	O
the	O
AVO	O
and	O
serial	O
printer	O
port	O
options	O
pre-installed	O
.	O
</s>
<s>
The	O
VT105	O
contained	O
a	O
simple	O
graphics	O
subsystem	O
known	O
as	O
waveform	O
graphics	O
which	O
was	O
mostly	O
compatible	O
with	O
same	O
system	O
in	O
the	O
earlier	O
VT55	B-Application
.	O
</s>
<s>
The	O
VT125	O
added	O
an	O
implementation	O
of	O
the	O
byte-efficient	O
Remote	O
Graphic	O
Instruction	O
Set	O
(	O
ReGIS	B-Application
)	O
,	O
which	O
used	O
custom	O
ANSI	O
codes	O
to	O
send	O
graphics	O
commands	O
to	O
the	O
terminal	B-General_Concept
,	O
rather	O
than	O
requiring	O
the	O
terminal	B-General_Concept
to	O
be	O
set	O
to	O
a	O
separate	O
less-efficient	O
graphics	O
mode	O
like	O
the	O
VT105	O
.	O
</s>
<s>
The	O
VT131	O
added	O
block	O
mode	O
support	O
,	O
allowing	O
a	O
form	O
to	O
be	O
sent	O
to	O
the	O
terminal	B-General_Concept
and	O
filled	O
in	O
locally	O
by	O
the	O
user	O
,	O
and	O
then	O
sending	O
the	O
contents	O
of	O
the	O
fields	O
in	O
the	O
form	O
back	O
to	O
the	O
host	B-Application
when	O
the	O
form	O
is	O
filled	O
in	O
.	O
</s>
<s>
The	O
VT100	B-Device
form	O
factor	O
left	O
significant	O
physical	O
space	O
in	O
the	O
case	O
for	O
expansion	O
,	O
and	O
DEC	O
used	O
this	O
to	O
produce	O
several	O
all-in-one	O
stand-alone	O
minicomputer	B-Architecture
systems	O
.	O
</s>
<s>
The	O
VT103	O
included	O
a	O
cardcage	O
and	O
4×4	O
(	O
8-slot	O
)	O
Q-Bus	B-Architecture
backplane	O
,	O
sufficient	O
to	O
configure	O
a	O
small	O
16-bit	O
LSI-11	O
microcomputer	O
system	O
within	O
the	O
case	O
,	O
and	O
supported	O
an	O
optional	O
dual	O
TU58	O
DECtape	O
II	O
block-addressable	O
cartridge	O
tape	O
drive	O
which	O
could	O
be	O
used	O
like	O
a	O
very	O
slow	O
disk	O
drive	O
.	O
</s>
<s>
The	O
VT180	B-Application
(	O
codenamed	O
"	O
Robin	O
"	O
)	O
added	O
a	O
single-board	O
microcomputer	O
using	O
a	O
Zilog	B-General_Concept
Z80	I-General_Concept
to	O
run	O
the	O
CP/M	B-Application
operating	I-Application
system	I-Application
.	O
</s>
<s>
The	O
VT278	O
(	O
DECmate	B-Device
)	O
added	O
a	O
small	O
PDP-8	B-Device
processor	B-Device
,	O
allowing	O
the	O
terminal	B-General_Concept
to	O
run	O
Digital	O
's	O
WPS-8	B-Protocol
word	O
processing	O
software	O
.	O
</s>
