Added running average methods to determine if we should send temperature / humidity reports

Author: tbowmo

libraries/MySensors/examples/SensebenderMicro/SensebenderMicro.ino

@@ -14,27 +14,30 @@
 #include <EEPROM.h>  
 #include <sha204_lib_return_codes.h>
 #include <sha204_library.h>
+#include <RunningAverage.h>
+#include <avr/power.h>
 
 // Define a static node address, remove if you want auto address assignment
 //#define NODE_ADDRESS   3
 
-#define RELEASE "1.1"
+#define RELEASE "1.2"
+
+#define AVERAGES 2
 
 // Child sensor ID's
 #define CHILD_ID_TEMP  1
 #define CHILD_ID_HUM   2
-#define CHILD_ID_BATT  199
 
 // How many milli seconds between each measurement
-#define MEASURE_INTERVAL 60000
+#define MEASURE_INTERVAL 1000
 
 // FORCE_TRANSMIT_INTERVAL, this number of times of wakeup, the sensor is forced to report all values to the controller
 #define FORCE_TRANSMIT_INTERVAL 30 
 
 // When MEASURE_INTERVAL is 60000 and FORCE_TRANSMIT_INTERVAL is 30, we force a transmission every 30 minutes.
 // Between the forced transmissions a tranmission will only occur if the measured value differs from the previous measurement
 
-//Pin definitions
+// Pin definitions
 #define TEST_PIN       A0
 #define LED_PIN        A2
 #define ATSHA204_PIN   17 // A3
@@ -50,25 +53,32 @@ MySensor gw;
 // Sensor messages
 MyMessage msgHum(CHILD_ID_HUM, V_HUM);
 MyMessage msgTemp(CHILD_ID_TEMP, V_TEMP);
-MyMessage msgBattery(CHILD_ID_BATT, V_VOLTAGE);
 
 // Global settings
 int measureCount = 0;
+int sendBattery = 0;
 boolean isMetric = true;
 
 // Storage of old measurements
 float lastTemperature = -100;
 int lastHumidity = -100;
 long lastBattery = -100;
 
-bool highfreq = true;
+RunningAverage raHum(AVERAGES);
+RunningAverage raTemp(AVERAGES);
 
+/****************************************************
+ *
+ * Setup code 
+ *
+ ****************************************************/
 void setup() {
-
+//  clock_prescale_set(clock_div_8); // Switch to 1Mhz right after powerup.
+  
   pinMode(LED_PIN, OUTPUT);
   digitalWrite(LED_PIN, LOW);
 
-  Serial.begin(115200);
+  Serial.begin(19200);
   Serial.print(F("Sensebender Micro FW "));
   Serial.print(RELEASE);
   Serial.flush();
@@ -79,6 +89,10 @@ void setup() {
   digitalWrite(TEST_PIN, HIGH); // Enable pullup
   if (!digitalRead(TEST_PIN)) testMode();
 
+  // Make sure that ATSHA204 is not floating
+  pinMode(ATSHA204_PIN, INPUT);
+  digitalWrite(ATSHA204_PIN, HIGH);
+  
   digitalWrite(TEST_PIN,LOW);
   digitalWrite(LED_PIN, HIGH); 
 
@@ -99,52 +113,75 @@ void setup() {
   gw.present(CHILD_ID_HUM,S_HUM);
 
   isMetric = gw.getConfig().isMetric;
-  Serial.print("isMetric: "); Serial.println(isMetric);
-
+  Serial.print(F("isMetric: ")); Serial.println(isMetric);
+  raHum.clear();
+  raTemp.clear();
+  sendTempHumidityMeasurements(false);
 }
 
 
-// Main loop function
+/***********************************************
+ *
+ *  Main loop function
+ *
+ ***********************************************/
 void loop() {
   measureCount ++;
+  sendBattery ++;
   bool forceTransmit = false;
-
-  // When we wake up the 5th time after power on, switch to 1Mhz clock
-  // This allows us to print debug messages on startup (as serial port is dependend on oscilator settings).
-  if ((measureCount == 5) && highfreq) switchClock(1<<CLKPS2); // Switch to 1Mhz for the reminder of the sketch, save power.
 
   if (measureCount > FORCE_TRANSMIT_INTERVAL) { // force a transmission
     forceTransmit = true; 
     measureCount = 0;
   }
 
   gw.process();
-  sendBattLevel(forceTransmit);
+
   sendTempHumidityMeasurements(forceTransmit);
+  if (sendBattery > 60) 
+  {
+     sendBattLevel(forceTransmit); // Not needed to send battery info that often
+     sendBattery = 0;
+  }
 
   gw.sleep(MEASURE_INTERVAL);  
 }
 
-/*
+
+/*********************************************
+ *
  * Sends temperature and humidity from Si7021 sensor
  *
  * Parameters
  * - force : Forces transmission of a value (even if it's the same as previous measurement)
- */
+ *
+ *********************************************/
 void sendTempHumidityMeasurements(bool force)
 {
-  if (force) {
-    lastHumidity = -100;
-    lastTemperature = -100;
-  }
+  bool tx = force;
 
   si7021_env data = humiditySensor.getHumidityAndTemperature();
+  float oldAvgTemp = raTemp.getAverage();
+  float oldAvgHum = raHum.getAverage();
 
-  float temperature = (isMetric ? data.celsiusHundredths : data.fahrenheitHundredths) / 100.0;
-    
-  int humidity = data.humidityPercent;
+  raTemp.addValue(data.celsiusHundredths / 100);
+  raHum.addValue(data.humidityPercent);
+  
+  float diffTemp = abs(oldAvgTemp - raTemp.getAverage());
+  float diffHum = abs(oldAvgHum - raHum.getAverage());
+
+  Serial.println(diffTemp);
+  Serial.println(diffHum); 
+
+  if (isnan(diffTemp)) tx = true; 
+  if (diffTemp > 0.2) tx = true;
+  if (diffHum > 0.5) tx = true;
 
-  if ((lastTemperature != temperature) | (lastHumidity != humidity)) {
+  if (tx) {
+    measureCount = 0;
+    float temperature = (isMetric ? data.celsiusHundredths : data.fahrenheitHundredths) / 100.0;
+     
+    int humidity = data.humidityPercent;
     Serial.print("T: ");Serial.println(temperature);
     Serial.print("H: ");Serial.println(humidity);
 
@@ -155,12 +192,14 @@ void sendTempHumidityMeasurements(bool force)
   }
 }
 
-/*
- * Sends battery information (both voltage, and battery percentage)
+/********************************************
+ *
+ * Sends battery information (battery percentage)
  *
  * Parameters
  * - force : Forces transmission of a value
- */
+ *
+ *******************************************/
 void sendBattLevel(bool force)
 {
   if (force) lastBattery = -1;
@@ -176,6 +215,11 @@ void sendBattLevel(bool force)
   }
 }
 
+/*******************************************
+ *
+ * Internal battery ADC measuring 
+ *
+ *******************************************/
 long readVcc() {
   // Read 1.1V reference against AVcc
   // set the reference to Vcc and the measurement to the internal 1.1V reference
@@ -202,18 +246,11 @@ long readVcc() {
   return result; // Vcc in millivolts
 }
 
-void switchClock(unsigned char clk)
-{
-  cli();
-  
-  CLKPR = 1<<CLKPCE; // Set CLKPCE to enable clk switching
-  CLKPR = clk;  
-  sei();
-  highfreq = false;
-}
-
-
-// Verify all peripherals, and signal via the LED if any problems.
+/****************************************************
+ *
+ * Verify all peripherals, and signal via the LED if any problems.
+ *
+ ****************************************************/
 void testMode()
 {
   uint8_t rx_buffer[SHA204_RSP_SIZE_MAX];

libraries/RunningAverage/RunningAverage.cpp

@@ -0,0 +1,101 @@
+//
+//    FILE: RunningAverage.cpp
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.2.08
+//    DATE: 2015-apr-10
+// PURPOSE: RunningAverage library for Arduino
+//
+// The library stores N individual values in a circular buffer,
+// to calculate the running average.
+//
+// HISTORY:
+// 0.1.00 - 2011-01-30 initial version
+// 0.1.01 - 2011-02-28 fixed missing destructor in .h
+// 0.2.00 - 2012-??-?? Yuval Naveh added trimValue (found on web)
+//          http://stromputer.googlecode.com/svn-history/r74/trunk/Arduino/Libraries/RunningAverage/RunningAverage.cpp
+// 0.2.01 - 2012-11-21 refactored
+// 0.2.02 - 2012-12-30 refactored trimValue -> fillValue
+// 0.2.03 - 2013-11-31 getElement
+// 0.2.04 - 2014-07-03 added memory protection
+// 0.2.05 - 2014-12-16 changed float -> double
+// 0.2.06 - 2015-03-07 all size uint8_t
+// 0.2.07 - 2015-03-16 added getMin() and getMax() functions (Eric Mulder)
+// 0.2.08 - 2015-04-10 refactored getMin() and getMax() implementation
+//
+// Released to the public domain
+//
+
+#include "RunningAverage.h"
+#include <stdlib.h>
+
+RunningAverage::RunningAverage(uint8_t size)
+{
+    _size = size;
+    _ar = (double*) malloc(_size * sizeof(double));
+    if (_ar == NULL) _size = 0;
+    clear();
+}
+
+RunningAverage::~RunningAverage()
+{
+    if (_ar != NULL) free(_ar);
+}
+
+// resets all counters
+void RunningAverage::clear()
+{
+    _cnt = 0;
+    _idx = 0;
+    _sum = 0.0;
+    _min = NAN;
+    _max = NAN;
+    for (uint8_t i = 0; i < _size; i++)
+    {
+        _ar[i] = 0.0; // keeps addValue simple
+    }
+}
+
+// adds a new value to the data-set
+void RunningAverage::addValue(double value)
+{
+    if (_ar == NULL) return;  // allocation error
+    _sum -= _ar[_idx];
+    _ar[_idx] = value;
+    _sum += _ar[_idx];
+    _idx++;
+    if (_idx == _size) _idx = 0;  // faster than %
+    // handle min max
+    if (_cnt == 0) _min = _max = value;
+    else if (value < _min) _min = value;
+    else if (value > _max) _max = value;
+    // update count as last otherwise if( _cnt == 0) above will fail
+    if (_cnt < _size) _cnt++;
+}
+
+// returns the average of the data-set added sofar
+double RunningAverage::getAverage()
+{
+    if (_cnt == 0) return NAN;
+    return _sum / _cnt;
+}
+
+// returns the value of an element if exist, NAN otherwise
+double RunningAverage::getElement(uint8_t idx)
+{
+    if (idx >=_cnt ) return NAN;
+    return _ar[idx];
+}
+
+// fill the average with a value
+// the param number determines how often value is added (weight)
+// number should preferably be between 1 and size
+void RunningAverage::fillValue(double value, uint8_t number)
+{
+    clear(); // TODO conditional?  if (clr) clear();
+
+    for (uint8_t i = 0; i < number; i++)
+    {
+        addValue(value);
+    }
+}
+// END OF FILE

libraries/RunningAverage/RunningAverage.h

@@ -0,0 +1,56 @@
+//
+//    FILE: RunningAverage.h
+//  AUTHOR: Rob dot Tillaart at gmail dot com
+// VERSION: 0.2.08
+//    DATE: 2015-apr-10
+// PURPOSE: RunningAverage library for Arduino
+//     URL: http://arduino.cc/playground/Main/RunningAverage
+// HISTORY: See RunningAverage.cpp
+//
+// Released to the public domain
+//
+// backwards compatibility
+// clr()   clear()
+// add(x)  addValue(x)
+// avg()   getAverage()
+
+#ifndef RunningAverage_h
+#define RunningAverage_h
+
+#define RUNNINGAVERAGE_LIB_VERSION "0.2.08"
+
+#include "Arduino.h"
+
+class RunningAverage
+{
+public:
+    RunningAverage(void);
+    RunningAverage(uint8_t);
+    ~RunningAverage();
+
+    void clear();
+    void addValue(double);
+    void fillValue(double, uint8_t);
+
+    double getAverage();
+    // returns lowest value added to the data-set since last clear
+    double getMin() { return _min; };
+    // returns highest value added to the data-set since last clear
+    double getMax() { return _max; };
+
+    double getElement(uint8_t idx);
+    uint8_t getSize() { return _size; }
+    uint8_t getCount() { return _cnt; }
+
+protected:
+    uint8_t _size;
+    uint8_t _cnt;
+    uint8_t _idx;
+    double _sum;
+    double * _ar;
+    double _min;
+    double _max;
+};
+
+#endif
+// END OF FILE