<s>
Color	B-Language
BASIC	I-Language
is	O
the	O
implementation	O
of	O
Microsoft	B-Language
BASIC	I-Language
that	O
is	O
included	O
in	O
the	O
ROM	B-Device
of	O
the	O
Tandy/Radio	O
Shack	O
TRS-80	B-Device
Color	I-Device
Computers	I-Device
manufactured	O
between	O
1980	O
and	O
1991	O
.	O
</s>
<s>
Color	B-Language
BASIC	I-Language
is	O
interpreted	B-Application
,	O
that	O
is	O
,	O
decoded	O
as	O
it	O
is	O
run	O
.	O
</s>
<s>
The	O
nucleus	O
of	O
Color	B-Language
BASIC	I-Language
was	O
Microsoft	O
BASIC-69	O
which	O
Tandy	O
licensed	O
from	O
Microsoft	O
.	O
</s>
<s>
Color	B-Language
BASIC	I-Language
1.0	O
was	O
released	O
with	O
the	O
original	O
4k	O
TRS-80	B-Device
Color	I-Device
Computer	I-Device
in	O
1980	O
.	O
</s>
<s>
It	O
resides	O
on	O
8k	O
bytes	O
of	O
ROM	B-Device
,	O
and	O
is	O
responsible	O
for	B-Language
all	O
'	O
housekeeping	O
 '	O
duties	O
on	O
the	O
system	O
.	O
</s>
<s>
Like	O
most	O
implementations	O
of	O
BASIC	O
,	O
each	O
line	O
of	O
code	O
starts	O
with	O
a	O
line	B-Application
number	I-Application
and	O
consists	O
of	O
one	O
or	O
more	O
statements	O
with	O
variables	O
and	O
operators	O
.	O
</s>
<s>
16k	O
of	O
memory	O
is	O
required	O
for	B-Language
the	O
next	O
level	O
of	O
BASIC	O
,	O
Extended	O
Color	B-Language
BASIC	I-Language
.	O
</s>
<s>
(	O
"	O
ECB	O
"	O
)	O
Extended	O
BASIC	O
is	O
required	O
for	B-Language
the	O
floppy	O
disk	O
controller	O
,	O
which	O
then	O
gives	O
you	O
Disk	O
Extended	O
Color	B-Language
BASIC	I-Language
.	O
</s>
<s>
(	O
"	O
DECB	O
"	O
)	O
Emulators	O
of	O
the	O
Color	B-Device
Computers	I-Device
running	O
this	O
interpreter	B-Application
and	O
the	O
others	O
are	O
available	O
for	B-Language
modern	O
computers	O
,	O
some	O
of	O
which	O
require	O
a	O
"	O
snapshot	O
"	O
file	O
of	O
the	O
physical	O
machine	O
.	O
</s>
<s>
Color	B-Language
BASIC	I-Language
understands	O
one	O
type	O
of	O
numeric	O
variable	O
and	O
string	O
variables	O
.	O
</s>
<s>
Variable	O
names	O
in	O
Color	B-Language
BASIC	I-Language
have	O
the	O
first	O
two	O
characters	O
significant	O
.	O
</s>
<s>
Unlike	O
most	O
implementations	O
of	O
Microsoft	B-Language
BASIC	I-Language
,	O
Color	B-Language
BASIC	I-Language
requires	O
the	O
user	O
to	O
reserve	O
space	O
for	B-Language
string	O
variables	O
via	O
the	O
CLEAR	O
statement	O
.	O
</s>
<s>
Color	B-Language
BASIC	I-Language
provides	O
several	O
operators	O
for	B-Language
both	O
mathematic	O
and	O
,	O
to	O
a	O
lesser	O
extent	O
,	O
string	O
operations	O
.	O
</s>
<s>
For	B-Language
testing	O
,	O
the	O
following	O
operators	O
are	O
used	O
:	O
</s>
<s>
In	O
Color	B-Language
BASIC	I-Language
,	O
device	O
#	O
-1	O
(	O
cassette	O
)	O
and	O
#	O
-2	O
(	O
printer	O
)	O
are	O
available	O
to	O
the	O
programmer	O
.	O
</s>
<s>
'	O
s	O
 '	O
searches	O
for	B-Language
the	O
next	O
instance	O
of	O
a	O
character	O
.	O
</s>
<s>
For	B-Language
the	O
'	O
s	O
 '	O
,	O
'	O
c	O
 '	O
and	O
'	O
d	O
 '	O
commands	O
you	O
can	O
also	O
enter	O
a	O
number	O
( #	O
)	O
before	O
pressing	O
any	O
of	O
them	O
which	O
will	O
:	O
'	O
s	O
 '	O
-	O
search	O
for	B-Language
the	O
#	O
instance	O
of	O
the	O
character	O
,	O
'	O
c	O
 '	O
-	O
allow	O
you	O
to	O
change	O
#	O
of	O
characters	O
,	O
'	O
d	O
 '	O
-	O
delete	O
#	O
amount	O
characters	O
.	O
</s>
<s>
INSTR(startpos,search str,target str )	O
searches	O
for	B-Language
the	O
first	O
string	O
,	O
in	O
the	O
target	O
str	O
.	O
</s>
<s>
INPUT	O
[	O
device	O
number ]	O
[ {	O
prompt	O
text}	O
;]	O
variable	O
[	O
,	O
variable	O
2	O
,	O
variable	O
n ]	O
Waits	O
for	B-Language
input	O
from	O
device	O
number	O
.	O
</s>
<s>
FM	O
bad	O
file	O
mode	O
,	O
attempt	O
to	O
INPUT	O
data	O
to	O
a	O
file	O
open	O
for	B-Language
OUTPUT	O
,	O
etc	O
.	O
</s>
<s>
There	O
are	O
a	O
few	O
subroutines	O
available	O
for	B-Language
machine	O
language	O
programs	O
in	O
the	O
Color	B-Language
BASIC	I-Language
ROM	B-Device
that	O
are	O
available	O
for	B-Language
general	O
purpose	O
programming	O
.	O
</s>
