mhz16: Initial implementation

This library implements support for the MHZ16 CO2 sensor.

Signed-off-by: Jon Trulson <jtrulson@ics.com>
Signed-off-by: Zion Orent <zorent@ics.com>
Signed-off-by: John Van Drasek <john.r.van.drasek@intel.com>

examples/c++/mhz16.cxx

@@ -0,0 +1,83 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 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.
+ */
+
+#include <unistd.h>
+#include <iostream>
+#include <signal.h>
+#include "mhz16.h"
+
+using namespace std;
+
+bool shouldRun = true;
+
+void sig_handler(int signo)
+{
+  if (signo == SIGINT)
+    shouldRun = false;
+}
+
+int main (int argc, char **argv)
+{
+  signal(SIGINT, sig_handler);
+
+//! [Interesting]
+  // Instantiate a MHZ16 serial CO2 sensor on uart 0.
+  // This example was tested on the Grove CO2 sensor module.
+
+  upm::MHZ16* co2 = new upm::MHZ16(0);
+  
+  // make sure port is initialized properly.  9600 baud is the default.
+  if (!co2->setupTty(B9600))
+    {
+      cerr << "Failed to setup tty port parameters" << endl;
+      return 1;
+    }
+  
+  cout << "Make sure that the sensor has had at least 3 minutes to warm up" 
+       << endl;
+  cout << "or you will not get valid results." << endl;
+  cout << "The temperature reported is not the ambient temperature, " << endl;
+  cout << "but rather the temperature of the sensor elements." << endl;
+
+  sleep(1);
+
+  int gas;
+  int temp;
+
+  while (shouldRun)
+    {
+      co2->getData(&gas, &temp);
+      cout << "CO2 concentration: " << gas << " PPM, "
+           << "Temperature (in C): " << temp <<endl;
+
+      sleep(2);
+    }
+
+//! [Interesting]
+
+  cout << "Exiting..." << endl;
+
+  delete co2;
+  return 0;
+}