ACT apricot - Page 247

SCREEN DRIVER
Note that 31 must be added to these values. For
example, suppose
you wanted to make the
screen a 20 character square in the top left-hand
corner. You
would do this:
PRINT CHR$(27) + "," + CHR$ ( 1+31) +
CHR$(20+31) +CHR$(1+31) +CHR$(20+31)
* 2D Clear all the characters displayed in normal,
low in tensi ty (see code 29).
* 2E Reset the size of the video screen, revokes the
parameters passed using code 2C.
* 2F / Set the membrane LED's - see the section on
the MicroScreen for more information.
30 0 Set the underline attribute on all characters
printed from now on, so now everything
printed will be underlined.
31 1 Reset the underline status so that characters
will not be underlined when printed.
32 2 Set the blink attribute for the block or
underline cursor, so it will flash on and off
approximately 3 times each second.
33 3 Switches the cursor blink off.
34 4 Change the value of a key on the keyboard.
Three arguments are passed:
1. The mode. From 1 t03.
1 is normal
2 is shifted
3
is control
2. The key number. An ASCII value in the
range 0 to 95