hka5: Initial implementation

This module implements support for the DFRobot Laser PM2.5 Sensor.  It
connects to a UART at 9600 baud.  This is the only baud rate
supported.  It optionally supports Reset and Set/Sleep gpios as well.

Signed-off-by: Jon Trulson <jtrulson@ics.com>

examples/javascript/hka5.js

@@ -0,0 +1,63 @@
+/*jslint node:true, vars:true, bitwise:true, unparam:true */
+/*jshint unused:true */
+
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2016 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+var sensorObj = require('jsupm_hka5');
+
+// Instantiate a HKA5 sensor on uart 0.  We don't use the set or
+// reset pins, so we pass -1 for them.
+var sensor = new sensorObj.HKA5(0, -1, -1);
+
+// update once every 2 seconds and output data
+setInterval(function()
+{
+    sensor.update()
+
+    console.log("PM 1  : "
+                + sensor.getPM1()
+                + " ug/m3");
+
+    console.log("PM 2.5: "
+                + sensor.getPM2_5()
+                + " ug/m3");
+
+    console.log("PM 10 : "
+                + sensor.getPM10()
+                + " ug/m3");
+
+    console.log();
+
+}, 2000);
+
+// exit on ^C
+process.on('SIGINT', function()
+{
+    sensor = null;
+    sensorObj.cleanUp();
+    sensorObj = null;
+    console.log("Exiting.");
+    process.exit(0);
+});