LEGO MINDSTORMS Robots, Manual, Page: 70 / 226

Page 73
start taskname
This command starts the named task.
stop taskname
Use this command to stop the named task.
The following program controls its outputs from
main
and uses another task,
sing
, to play some music. The
sing
task has to be started from
main
; otherwise, its commands will never be
executed.
task main() {
start sing;
while (true) {
OnFwd(OUT_A);
OnRev(OUT_C);
Wait(100);
OnFwd(OUT_C);
OnRev(OUT_A);
Wait(100);
}
}
#define SIXTH 12
#define HALF 3
∗
SIXTH
#define BEAT 2
∗
HALF
#define GRACE 6
task sing() {
PlayTone(330, 2
∗
BEAT);
Wait(2
∗
BEAT + 2
∗
SIXTH);
PlayTone(115, SIXTH);
PlayTone(208, SIXTH);
PlayTone(247, SIXTH);
PlayTone(330, SIXTH);
PlayTone(311, 2
∗
BEAT);
Wait(4
∗
SIXTH + 2
∗
BEAT + 2
∗
SIXTH);
PlayTone(115, SIXTH);
PlayTone(208, SIXTH);
PlayTone(247, SIXTH);
PlayTone(311, SIXTH);
PlayTone(277, 3
∗
BEAT);
Wait(4
∗
SIXTH + 3
∗
BEAT + HALF);
PlayTone(277, HALF);
PlayTone(311, HALF);
PlayTone(370, GRACE);
PlayTone(330, HALF);
PlayTone(311, HALF); Wait (2
∗
HALF);
PlayTone(277, HALF);
PlayTone(330, HALF);
PlayTone(220, HALF);
PlayTone(220, 2
∗
BEAT);
Wait(GRACE + 5
∗
HALF + 2
∗
BEAT + HALF);
PlayTone(247, HALF);