Adds soundLevel

To be replaced by pxt-common-packages when DAL is updated.

libs/core/input.ts

@@ -77,4 +77,27 @@ namespace input {
     export function runningTimeMicros() {
         return control.micros();
     }
+
+    /**
+     * gets the level of loudness in 0-100%
+     */
+    //% blockId="loudness"
+    //% block="Loudness"
+
+    export function soundLevel(): number {
+        let value = 0
+        let max = 0
+        let min = 1023
+        for (let index = 0; index < 32; index++) {
+            value = pins.analogReadPin(AnalogPin.MIC)
+            if (value > max) {
+                max = value
+            } else if (value < min) {
+                min = value
+            }
+        }
+        value = (max - min) * 977 / 10000
+        return value
+    }
+
 }