separate alpha Example

10    MERGE ALPHA WITH GRAPHICS
20    CLEAR SCREEN
30    PRINT "With Alpha and Graphics merged, the text and"
40    PRINT "graphics should disappear with a CLEAR SCREEN"
50    PAUSE
60    MOVE 0,60
70    AREA PEN 4
80    RECTANGLE 30,30,FILL
90    WAIT 2
100   SEPARATE ALPHA FROM GRAPHICS
110   CLEAR SCREEN
120   PRINT "This text should disappear with a CLEAR SCREEN"
130   PRINT "The square should not be erased"
140   MOVE 0,60
150   AREA PEN 7
160   RECTANGLE 30,30,FILL
170   WAIT 2
180   CLEAR SCREEN
190   WAIT 1
200   PRINT "Notice the square is not erased!"
210   END