Create AirQualityCO2

moved the file

Author: empierre

libraries/MySensors/examples/CO2Sensor/AirQualityCO2

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+/**
+ * The MySensors Arduino library handles the wireless radio link and protocol
+ * between your home built sensors/actuators and HA controller of choice.
+ * The sensors forms a self healing radio network with optional repeaters. Each
+ * repeater and gateway builds a routing tables in EEPROM which keeps track of the
+ * network topology allowing messages to be routed to nodes.
+ *
+ * Created by Henrik Ekblad <[email protected]>
+ * Copyright (C) 2013-2015 Sensnology AB
+ * Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
+ *
+ * Documentation: http://www.mysensors.org
+ * Support Forum: http://forum.mysensors.org
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ *******************************
+ *
+ * DESCRIPTION
+ *
+ *  MH-Z14 CO2 sensor
+ * 
+ *  Wiring:
+ *   Pad 1, Pad 5: Vin (Voltage input 4.5V-6V) 
+ *   Pad 2, Pad 3, Pad 12: GND 
+ *   Pad 6: PWM output ==> pin 6
+ *
+ *	From: http://davidegironi.blogspot.fr/2014/01/co2-meter-using-ndir-infrared-mh-z14.html
+ * 	  MH-Z14 has a PWM output, with a sensitivity range of 0ppm to 2000ppm CO2, an accurancy of ±200ppm.
+ * 	  The cycle is 1004ms±5%, given the duty cicle Th (pulse high), Tl is 1004-Th, we can convert it to CO2 value using the formula:
+ *	  CO2ppm = 2000 * (Th - 2ms) /(Th + Tl - 4ms)
+ * 	From: http://airqualityegg.wikispaces.com/Sensor+Tests
+ *	  - response time is less than 30 s
+ *   - 3 minute warm up time
+ *	datasheet: http://www.futurlec.com/Datasheet/Sensor/MH-Z14.pdf
+* Contributor: epierre
+**/
+
+
+#include <MySensor.h>  
+#include <SPI.h>
+
+#define CHILD_ID_AIQ 0
+#define AIQ_SENSOR_ANALOG_PIN 6
+
+unsigned long SLEEP_TIME = 30*1000; // Sleep time between reads (in milliseconds)
+
+float valAIQ =0.0;
+float lastAIQ =0.0;
+
+MySensor gw;
+MyMessage msg(CHILD_ID_AIQ, V_LEVEL);
+MyMessage msg2(CHILD_ID_AIQ, V_UNIT_PREFIX);
+
+void setup()  
+{
+  gw.begin();
+
+  // Send the sketch version information to the gateway and Controller
+  gw.sendSketchInfo("AIQ Sensor CO2 MH-Z14", "1.0");
+
+  // Register all sensors to gateway (they will be created as child devices)
+  gw.present(CHILD_ID_AIQ, S_AIR_QUALITY);  
+  gw.send(msg2.set("ppm"));
+  
+  gw.sleep(SLEEP_TIME);
+  
+  pinMode(AIQ_SENSOR_ANALOG_PIN, INPUT);
+   
+}
+
+void loop() { 
+
+  //unsigned long duration = pulseIn(AIQ_SENSOR_ANALOG_PIN, HIGH);
+  while(digitalRead(AIQ_SENSOR_ANALOG_PIN) == HIGH) {;}
+  //wait for the pin to go HIGH and measure HIGH time
+  unsigned long duration = pulseIn(AIQ_SENSOR_ANALOG_PIN, HIGH);
+  
+  //Serial.print(duration/1000); Serial.println(" ms ");
+  //from datasheet
+	//CO2 ppm = 2000 * (Th - 2ms) / (Th + Tl - 4ms)
+	//  given Tl + Th = 1004
+	//        Tl = 1004 - Th
+	//        = 2000 * (Th - 2ms) / (Th + 1004 - Th -4ms)
+	//        = 2000 * (Th - 2ms) / 1000 = 2 * (Th - 2ms)
+  long co2ppm = 2 * ((duration/1000) - 2);
+  //Serial.print(co2ppm);
+  if ((co2ppm != lastAIQ)&&(abs(co2ppm-lastAIQ)>=10)) {
+      gw.send(msg.set((long)ceil(co2ppm)));
+      lastAIQ = ceil(co2ppm);
+  }
+  
+  //Serial.println();
+  
+  // Power down the radio.  Note that the radio will get powered back up
+  // on the next write() call.
+  gw.sleep(SLEEP_TIME); //sleep for: sleepTime
+}