Add music

libs/music/music.cpp

@@ -0,0 +1,52 @@
+#include "pxt.h"
+#include "ev3.h"
+
+#define NOTE_PAUSE 20
+
+namespace music {
+
+byte currVolume = 100;
+
+/**
+* Set the output volume of the sound synthesizer.
+* @param volume the volume 0...256, eg: 128
+*/
+//% weight=96
+//% blockId=synth_set_volume block="set volume %volume"
+//% parts="speaker" blockGap=8
+//% volume.min=0 volume.max=256
+//% help=music/set-volume
+//% weight=1
+void setVolume(int volume) {
+    currVolume = max(0, min(100, volume * 100 / 256));
+}
+
+/**
+* Play a tone through the speaker for some amount of time.
+* @param frequency pitch of the tone to play in Hertz (Hz)
+* @param ms tone duration in milliseconds (ms)
+*/
+//% help=music/play-tone weight=90
+//% blockId=music_play_note block="play tone|at %note=device_note|for %duration=device_beat"
+//% parts="headphone" async blockGap=8
+//% blockNamespace=music
+void playTone(int frequency, int ms) {
+    if (frequency <= 0) {
+        StopSound();
+        if (ms >= 0)
+            sleep_ms(ms);
+    } else {
+        if (ms > 0) {
+            int d = max(1, ms - NOTE_PAUSE); // allow for short rest
+            int r = max(1, ms - d);
+            PlayToneEx(frequency, d, currVolume);
+            sleep_ms(d + r);
+        } else {
+            // ring
+            PlayToneEx(frequency, 60000, currVolume);
+        }
+    }
+    sleep_ms(1);
+}
+
+}