fix simulator support for music

sim/dalboard.ts

@@ -14,6 +14,7 @@ namespace pxsim {
         radioState: RadioState;
         neopixelState: NeoPixelState;
         rgbLedState: number;
+        speakerState: SpeakerState;
 
         constructor() {
             super()
@@ -59,6 +60,7 @@ namespace pxsim {
             this.builtinParts["lightsensor"] = this.lightSensorState = new LightSensorState();
             this.builtinParts["compass"] = this.compassState = new CompassState();
             this.builtinParts["neopixel"] = this.neopixelState = new NeoPixelState();
+            this.builtinParts["speaker"] = this.speakerState = new SpeakerState();
 
             this.builtinVisuals["buttonpair"] = () => new visuals.ButtonPairView();
             this.builtinVisuals["ledmatrix"] = () => new visuals.LedMatrixView();

sim/state/music.ts

@@ -0,0 +1,29 @@
+namespace pxsim {
+    export class SpeakerState {
+        frequency: number;
+        ms: number;
+    }
+    
+}
+namespace pxsim.music {
+
+    export function playTone(frequency: number, ms: number) {
+        const b = board();
+        b.speakerState.frequency = frequency;
+        b.speakerState.ms = ms;
+
+        runtime.queueDisplayUpdate();
+        let cb = getResume();
+        AudioContextManager.tone(frequency, 1);
+        if (ms <= 0) cb();
+        else {
+            setTimeout(() => {
+                AudioContextManager.stop();
+                b.speakerState.frequency = 0;
+                b.speakerState.ms = 0;
+                runtime.queueDisplayUpdate();
+                cb()
+            }, ms);
+        }
+    }
+}

sim/visuals/microbit.ts

@@ -1349,6 +1349,7 @@ namespace pxsim.visuals {
             this.updateButtonAB();
             this.updateGestures();
             this.updateRgbLed();
+			this.updateSpeaker();
 
             if (!runtime || runtime.dead) svg.addClass(this.element, "grayscale");
             else svg.removeClass(this.element, "grayscale");
@@ -1371,6 +1372,15 @@ namespace pxsim.visuals {
             }
         }
 
+		private updateSpeaker() {
+            let state = this.board;
+			if (state.speakerState.frequency) {
+				
+			} else {
+
+			}			
+		}
+
         private updateGestures() {
             let state = this.board;
             if (state.accelerometerState.useShake && !this.shakeButton) {