Radio Shack TRS-80 - Page 120

110
IF
Y<48
THEN
130
120
Y=Y-48
130
IF
YOKTHEN
80
999
GOTO
999
The
dot appears to
strike the
barrier and stick
to
it.
Now let's have the dot start in
the middle
and
ricochet
from both the top and
the bottom:
10 CLS
20
FOR
M=0 TO 127
30 SET (M,0)
40
SET
<M,47)
50 NEXT M
60
Y=14
70
D=l
80
RESET (64.Y+48-D)
90 SET<64 ,Y)
100
Y=Y+D
110
IF
Y=48
THEN 130
120 IF YO-1
THEN 80
130
Y=Y-2*D
140 D=-D
150
GOTO 90
999 GOTO 999
118