Radio Shack TRS-80 Model III - Video Display Usage

OPERATION
5
/
Using
the
Video Display
Character
Size
There
are
16 lines
on
the display,
and
two
character sizes: normal (64
characters per
line
—
"cpl"),
and
double-size,
or32
cpl.
The Computer
starts
in the
64
cpl
mode. To
change to 32 cpl,
press
(SHIFT)
R
in the
immediate
mode or
execute the
BASIC statement:
PRINT
CHR$(23)
To
return to
64 cpl,
press (CLEAR) in
the command
mode, or execute
the BASIC
statement:
CLS
Cursor
The cursor
indicates
the current display
position. When
you start
BASIC, the
cursor
is a blinking
block
.
You can
change the cursor
character and you
can make
it solid
(non-blinking).
Memory location
16412
contains
the blink/non-blink
status. When
it contains
a
zero
,
a blinking
cursor will
be used . When
it contains a non-zero
value
, a
non-blinking
cursor will
be used
.
For example,
to make
a solid cursor,
execute the BASIC
statement:
POKE 1641
2,1
To make
a blinking
cursor, execute
the BASIC statement:
POKE 1641
2,0
Memory
location
16419 contains the ASCII code of
the cursor character.
When
you
start
BASIC, this address
contains 176.
To change the cursor,
use the POKE
statement.
For example,
POKE
1641
9,
63
changes
the cursor to
a
"?",
since
63 is the ASCII code for a
question-mark.
23