LEGO MINDSTORMS Robots - Page 70

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);