<s>
The	O
VT320	B-Application
is	O
an	O
ANSI	O
standard	O
computer	B-General_Concept
terminal	I-General_Concept
introduced	O
by	O
Digital	O
Equipment	O
Corporation	O
(	O
DEC	O
)	O
in	O
1987	O
.	O
</s>
<s>
The	O
VT320	B-Application
is	O
the	O
text-only	O
version	O
,	O
while	O
the	O
VT330	B-Application
adds	O
monochrome	O
ReGIS	B-Application
,	O
Sixel	O
and	O
Tektronix	B-General_Concept
4010	I-General_Concept
graphics	O
,	O
and	O
the	O
VT340	B-Application
adds	O
color	O
.	O
</s>
<s>
The	O
300	O
series	O
replaced	O
the	O
earlier	O
VT200	B-Device
series	I-Device
,	O
as	O
a	O
lower-cost	O
system	O
better	O
able	O
to	O
compete	O
with	O
a	O
number	O
of	O
VT220	B-Device
clones	O
that	O
had	O
entered	O
the	O
market	O
.	O
</s>
<s>
Foremost	O
among	O
these	O
was	O
the	O
Wyse	O
WY-60	O
,	O
introduced	O
in	O
1986	O
with	O
a	O
form	O
factor	O
and	O
feature	O
set	O
similar	O
to	O
the	O
VT220	B-Device
,	O
but	O
including	O
4010	O
graphics	O
and	O
selling	O
for	O
only	O
$699	O
,	O
compared	O
to	O
$795	O
for	O
the	O
base-model	O
VT220	B-Device
lacking	O
graphics	O
.	O
</s>
<s>
The	O
VT320	B-Application
was	O
introduced	O
at	O
$495	O
,	O
something	O
of	O
a	O
surprise	O
,	O
forcing	O
Wyse	O
to	O
lower	O
their	O
prices	O
to	O
$599	O
.	O
</s>
<s>
The	O
VT320	B-Application
was	O
replaced	O
by	O
the	O
VT420	B-Application
in	O
1990	O
,	O
but	O
the	O
VT340	B-Application
remained	O
in	O
production	O
until	O
all	O
of	O
these	O
models	O
were	O
replaced	O
by	O
the	O
VT500	B-Application
series	I-Application
in	O
1994	O
.	O
</s>
<s>
With	O
the	O
great	O
increase	O
in	O
RAM	B-Architecture
available	O
,	O
the	O
300s	O
added	O
the	O
ability	O
to	O
store	O
several	O
pages	O
of	O
data	O
locally	O
,	O
as	O
well	O
as	O
perform	O
editing	O
on	O
that	O
data	O
entirely	O
within	O
the	O
terminal	O
.	O
</s>
<s>
That	O
memory	O
also	O
meant	O
all	O
of	O
the	O
300	O
series	O
were	O
able	O
to	O
store	O
large	O
numbers	O
of	O
sixel-based	O
glyphs	O
,	O
allowing	O
them	O
to	O
be	O
used	O
not	O
only	O
as	O
a	O
user-defined	O
character	B-General_Concept
set	I-General_Concept
as	O
in	O
the	O
earlier	O
200s	O
,	O
but	O
also	O
to	O
produce	O
full-screen	O
bitmap	B-Algorithm
graphics	I-Algorithm
by	O
storing	O
a	O
separate	O
sixel	O
for	O
each	O
location	O
on	O
the	O
screen	O
.	O
</s>
<s>
Finally	O
,	O
all	O
members	O
of	O
the	O
line	O
could	O
support	O
two	O
sessions	O
,	O
either	O
using	O
two	O
MMJ	O
ports	O
available	O
on	O
some	O
models	O
,	O
or	O
in	O
the	O
case	O
of	O
the	O
VT330	B-Application
and	O
VT340	B-Application
,	O
using	O
a	O
single	O
serial	O
connection	O
using	O
a	O
system	O
known	O
as	O
TD/SMP	O
on	O
the	O
server	O
and	O
SSU	O
on	O
the	O
terminals	O
.	O
</s>
<s>
The	O
TD/SMP	O
protocol	O
was	O
never	O
published	O
,	O
and	O
only	O
worked	O
with	O
DEC	O
's	O
own	O
terminal	B-Device
servers	I-Device
.	O
</s>
<s>
Like	O
the	O
VT200s	O
,	O
the	O
VT300s	O
included	O
a	O
number	O
of	O
alternate	O
character	B-General_Concept
sets	I-General_Concept
for	O
various	O
international	O
uses	O
and	O
basic	O
form	O
graphics	O
.	O
</s>
<s>
The	O
sets	O
were	O
ASCII	O
,	O
ISO	O
Latin	O
and	O
three	O
graphics	O
character	B-General_Concept
sets	I-General_Concept
.	O
</s>
<s>
The	O
system	O
also	O
included	O
DEC	O
's	O
unique	O
National	O
Replacement	O
Character	B-General_Concept
Sets	I-General_Concept
that	O
allowed	O
single	O
characters	O
in	O
a	O
set	O
to	O
be	O
swapped	O
out	O
to	O
match	O
the	O
layout	O
of	O
a	O
keyboard	B-Device
.	O
</s>
<s>
It	O
supported	O
the	O
full	O
range	O
of	O
ANSI	O
escape	O
codes	O
,	O
although	O
some	O
sources	O
state	O
it	O
did	O
not	O
decode	O
standard	O
color	O
sequences	O
even	O
on	O
the	O
VT340	B-Application
.	O
</s>
<s>
The	O
screen	O
itself	O
was	O
a	O
14-inch	O
CRT	B-Device
mounted	O
on	O
a	O
tilt	O
and	O
swivel	O
stand	O
.	O
</s>
<s>
The	O
VT330	B-Application
had	O
two	O
bit-planes	O
that	O
produced	O
4	O
shades	O
of	O
grey	O
,	O
while	O
the	O
VT340	B-Application
had	O
four	O
bit-planes	O
to	O
produce	O
16	O
colors	O
out	O
of	O
a	O
palette	O
of	O
4096	O
.	O
</s>
<s>
The	O
300s	O
could	O
be	O
set	O
to	O
VT100	B-Device
or	O
VT52	B-Application
mode	O
.	O
</s>
