<s>
The	O
ATASCII	B-Protocol
character	O
set	O
,	O
from	O
ATARI	O
Standard	O
Code	O
for	O
Information	O
Interchange	O
,	O
alternatively	O
ATARI	O
ASCII	B-Protocol
,	O
is	O
the	O
variation	O
on	O
ASCII	B-Protocol
used	O
in	O
the	O
Atari	B-Device
8-bit	I-Device
family	I-Device
of	O
home	O
computers	O
.	O
</s>
<s>
The	O
last	O
computer	O
to	O
use	O
the	O
ATASCII	B-Protocol
character	O
set	O
is	O
the	O
Atari	B-General_Concept
XEGS	I-General_Concept
which	O
was	O
released	O
in	O
1987	O
and	O
discontinued	O
in	O
1992	O
.	O
</s>
<s>
The	O
Atari	B-Device
ST	I-Device
family	O
of	O
computers	O
use	O
the	O
different	O
Atari	B-Device
ST	I-Device
character	O
set	O
.	O
</s>
<s>
Like	O
most	O
other	O
non-standard	O
ASCIIs	B-Protocol
,	O
ATASCII	B-Protocol
has	O
its	O
own	O
special	O
block	O
graphics	O
symbols	O
(	O
arrows	O
,	O
blocks	O
,	O
circles	O
,	O
line	O
segments	O
,	O
playing	O
card	O
suits	O
,	O
etc	O
.	O
)	O
</s>
<s>
corresponding	O
to	O
the	O
control	O
character	O
locations	O
of	O
the	O
standard	O
ASCII	B-Protocol
table	O
(	O
characters	O
031	O
)	O
,	O
and	O
a	O
few	O
other	O
character	O
locations	O
.	O
</s>
<s>
The	O
main	O
difference	O
between	O
standard	O
ASCII	B-Protocol
and	O
ATASCII	B-Protocol
is	O
the	O
use	O
of	O
control	O
characters	O
.	O
</s>
<s>
In	O
standard	O
ASCII	B-Protocol
,	O
a	O
character	O
in	O
the	O
range	O
0	O
to	O
31	O
is	O
construed	O
as	O
a	O
command	O
,	O
which	O
might	O
move	O
the	O
cursor	O
,	O
clear	O
the	O
screen	O
,	O
end	O
a	O
line	O
,	O
and	O
so	O
on	O
.	O
</s>
<s>
In	O
ATASCII	B-Protocol
most	O
of	O
the	O
ASCII	B-Protocol
control	O
character	O
values	O
produce	O
a	O
graphics	O
glyph	O
instead	O
.	O
</s>
<s>
ATASCII	B-Protocol
uses	O
character	O
values	O
different	O
from	O
ASCII	B-Protocol
for	O
cursor	O
control	O
.	O
</s>
<s>
ATASCII	B-Protocol
has	O
a	O
character	O
set	O
of	O
only	O
128	O
characters	O
.	O
</s>
<s>
If	O
the	O
high-order	O
bit	O
is	O
set	O
on	O
a	O
character	O
(	O
i.e.	O
,	O
if	O
the	O
byte	O
value	O
of	O
the	O
character	O
is	O
between	O
128	O
and	O
255	O
)	O
the	O
character	O
is	O
generally	O
rendered	O
in	O
the	O
reverse	O
video	O
(	O
also	O
called	O
"	O
inverse	O
video	O
"	O
)	O
of	O
its	O
counterpart	O
between	O
0	O
and	O
127	O
,	O
using	O
a	O
bitwise	O
negation	O
of	O
the	O
character	O
's	O
glyph	O
.	O
</s>
<s>
This	O
is	O
done	O
by	O
the	O
ANTIC	B-General_Concept
chip	O
.	O
</s>
<s>
The	O
two	O
exceptions	O
to	O
this	O
rule	O
are	O
that	O
an	O
"	O
escape	O
"	O
character	O
(	O
ATASCII	B-Protocol
and	O
ASCII	B-Algorithm
27	I-Algorithm
)	O
with	O
its	O
high	O
order	O
bit	O
set	O
becomes	O
an	O
"	O
EOL	O
"	O
or	O
"	O
End	O
Of	O
Line	O
"	O
character	O
(	O
ATASCII	B-Protocol
155	O
;	O
ASCII	B-Protocol
13	O
)	O
,	O
and	O
a	O
"	O
clear	O
screen	O
"	O
character	O
(	O
ATASCII	B-Protocol
125	O
)	O
with	O
its	O
high	O
order	O
bit	O
set	O
becomes	O
a	O
"	O
bell	O
"	O
or	O
"	O
buzzer	O
"	O
character	O
(	O
ATASCII	B-Protocol
253	O
;	O
ASCII	B-Protocol
7	O
)	O
.	O
</s>
<s>
The	O
ATASCII	B-Protocol
control	O
characters	O
used	O
by	O
the	O
screen	O
editor	O
for	O
cursor	O
control	O
(	O
arrow	O
keys	O
)	O
and	O
text	O
editing	O
(	O
tab	O
,	O
insert	O
,	O
delete	O
,	O
backspace	O
,	O
etc	O
.	O
)	O
</s>
<s>
have	O
associated	O
graphic	O
symbols	O
that	O
can	O
be	O
displayed	O
by	O
preceding	O
them	O
by	O
the	O
"	O
escape	O
"	O
character	O
(	O
ATASCII	B-Protocol
27	O
)	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
right	O
arrow	O
can	O
be	O
displayed	O
on	O
a	O
screen	O
or	O
printer	O
by	O
preceding	O
it	O
with	O
the	O
escape	B-Algorithm
character	I-Algorithm
followed	O
by	O
the	O
"	O
cursor	O
right	O
"	O
character	O
itself	O
(	O
ATASCII	B-Protocol
31	O
)	O
.	O
</s>
<s>
Cursor	O
movement	O
commands	O
(	O
and	O
even	O
carriage	O
returns	O
and	O
line	O
feeds	O
)	O
from	O
computers	O
not	O
using	O
ATASCII	B-Protocol
will	O
be	O
nonsense	O
on	O
an	O
Atari	O
,	O
and	O
vice	O
versa	O
.	O
</s>
<s>
Terminal	O
programs	O
need	O
to	O
translate	O
between	O
ATASCII	B-Protocol
and	O
standard	O
ASCII	B-Protocol
.	O
</s>
<s>
If	O
it	O
got	O
13	O
(	O
ASCII	B-Protocol
CR	O
)	O
,	O
then	O
standard	O
ASCII	B-Protocol
would	O
be	O
used	O
.	O
</s>
<s>
If	O
it	O
got	O
155	O
(	O
ATASCII	B-Protocol
CR	O
)	O
it	O
would	O
switch	O
to	O
ATASCII	B-Protocol
,	O
allowing	O
full	O
use	O
of	O
the	O
ATASCII	B-Protocol
graphic	O
set	O
.	O
</s>
<s>
Text	O
files	O
encoded	O
in	O
ATASCII	B-Protocol
also	O
need	O
conversion	O
to	O
be	O
viewed	O
on	O
modern	O
PCs	O
and	O
vice	O
versa	O
-	O
utilities	O
are	O
available	O
to	O
facilitate	O
this	O
.	O
</s>
<s>
The	O
control	O
codes	O
in	O
ATASCII	B-Protocol
are	O
transmissible	O
to	O
other	O
computers	O
such	O
as	O
BBS	B-Application
's	O
,	O
and	O
crude	O
animations	O
are	O
possible	O
.	O
</s>
<s>
Because	O
cursor	O
control	O
operations	O
are	O
represented	O
with	O
a	O
single	O
character	O
(	O
as	O
opposed	O
to	O
multi-byte	O
'	O
escape	O
 '	O
sequences	O
that	O
were	O
common	O
in	O
other	O
schemes	O
,	O
like	O
ANSI	B-Protocol
or	O
VT100	B-Device
)	O
,	O
it	O
is	O
quite	O
easy	O
to	O
make	O
these	O
animations	O
.	O
</s>
<s>
The	O
simple	O
capture	O
programs	O
did	O
n't	O
have	O
editing	O
features	O
,	O
so	O
ATASCII	B-Protocol
movies	O
frequently	O
had	O
errors	O
that	O
were	O
corrected	O
by	O
repositioning	O
the	O
cursor	O
and	O
printing	O
over	O
the	O
mistake	O
.	O
</s>
<s>
The	O
following	O
table	O
shows	O
the	O
ATASCII	B-Protocol
character	O
set	O
.	O
</s>
<s>
The	O
arrangement	O
of	O
glyphs	O
seems	O
to	O
make	O
little	O
sense	O
in	O
ATASCII	B-Protocol
order	O
,	O
however	O
the	O
arrangement	O
of	O
many	O
make	O
sense	O
when	O
the	O
QWERTY	O
keyboard	O
layout	O
is	O
taken	O
into	O
consideration	O
.	O
</s>
<s>
For	O
example	O
,	O
┌	O
,	O
┬	O
,	O
and	O
┐	O
are	O
the	O
control	O
graphics	O
characters	O
found	O
on	O
the	O
top	O
left	O
Q	B-Algorithm
,	O
W	B-Device
,	O
and	O
E	B-Language
keys	O
.	O
</s>
<s>
Atari	B-Device
8-bits	I-Device
,	O
via	O
the	O
ANTIC	B-General_Concept
coprocessor	O
,	O
supported	O
indirection	O
of	O
the	O
character	O
set	O
graphics	O
,	O
allowing	O
a	O
program	O
to	O
redefine	O
the	O
graphical	O
glyphs	O
that	O
appear	O
for	O
each	O
ATASCII	B-Protocol
character	O
.	O
</s>
<s>
Starting	O
with	O
the	O
Atari	O
1200XL	B-Device
,	O
the	O
first	O
in	O
the	O
XL	O
line	O
of	O
computers	O
that	O
followed	O
the	O
original	O
400	O
and	O
800	O
models	O
,	O
the	O
Atari	O
OS	O
ROM	O
included	O
a	O
so-called	O
"	O
international	O
"	O
character	O
set	O
,	O
that	O
replaced	O
29	O
of	O
the	O
graphical	O
glyphs	O
with	O
Latin	O
alphabetical	O
characters	O
containing	O
diacritics	O
,	O
such	O
as	O
e-acute	O
( é	O
)	O
.	O
</s>
<s>
The	O
OS	O
built	O
into	O
1200XL	B-Device
,	O
the	O
one	O
and	O
only	O
Atari	B-Device
8-bit	I-Device
model	O
with	O
function	O
keys	O
,	O
allowed	O
users	O
to	O
switch	O
between	O
the	O
standard	O
and	O
alternate	O
character	O
sets	O
by	O
pressing	O
.	O
</s>
<s>
Later	O
XL	O
and	O
XE	O
models	O
required	O
the	O
user	O
to	O
update	O
a	O
register	O
in	O
RAM	O
(	O
e.g.	O
,	O
via	O
a	O
POKE	O
command	O
in	O
BASIC	O
)	O
.	O
</s>
