adding keyboard control js - built on Feb 3rd meetup

Step1_Input_Output/S1_keyboard_led_piezo/keyboard–led-piezo.js

@@ -0,0 +1,46 @@
+
+var five = require("johnny-five");
+var keypress = require("keypress");
+var board = new five.Board();
+
+board.on("ready", function() {
+
+  // assign an LED from pin 11
+	var led = new five.Led(11);	
+  // original brightness accumulator
+	var newBrightness = 255;
+
+  // fires on key down from keyboard
+  function keypressDown(ch, key) {
+
+    // if a key exists
+    if (key) {
+      // pressing the up arrow
+      if (key.name === "up") {
+        // increase brightness by 20
+        newBrightness += 20;
+      }
+      // pressing the down arrow
+      if (key.name === "down") {
+        // reduce  brightness by 20
+       	newBrightness -= 20; 
+      }
+
+      // if brightness is less than the minimum, default to minimum
+      if (newBrightness <0 ) newBrightness = 0;
+      // if brightness is greater than the maximum, default to maximum
+      if (newBrightness >255 ) newBrightness = 255;
+
+      // assign new brightness to LED, transition for 250 milliseconds
+      led.fade(newBrightness, 250);
+    }
+  }
+
+  // keyboard accept standard in data
+	keypress(process.stdin);
+  // event listener
+  process.stdin.on("keypress", keypressDown);
+  // default brightness of LED
+  led.brightness( 255 );
+
+});