Domotiocz + Rain gauge

[TheoL]

@AWI A lesson learned a couple of month ago. When using an induction reed switch (some of them have a coil around the glass) always add a reversed diode. Otherwise the polarity of the reed switch is being turned for just a millisecond which is enough to cause the arduino to reset ;-). I'm still learning a lot about electronics.

At the moment the diode seems to work. No Arduino resetting for the last couple of hours.

Regarding to the pulse counter is seems to work perfectly. That way I don't need to store any values on the EPROM, which is something I prefer not to do. I just query the current pulse count from Domoticz when the sensors boots. Sending the total amount of rain is as easy as pulse count * bucket size. Not real rocket science.

[TheoL]

@sundberg84 Here's the first version of the sketch. Note that I don't use the sleep. My main goal for creating my own outside weather station is to get rid of the batteries. Because they always same to stop working whenever I'm not at home.

/*
 Arduino Tipping Bucket Rain Gauge, SI7021 Temperature + Humidity sensor

 Created October 2nd 2016
 Author by Theo

 This node uses a tipping bucket rain gauge for measuring rain fall. And a si7021 Temperature and Humidity sensor. The logic in
 this sketch might be specific for Domoticz, because of the Pulse counter.

 Based upon sketches created by @BulldogLowell / @PeteWill, @sundber84
 for free public use

 Hardware used:
 Arduino Pro Mini 3.3V
 buck converter
 nrf24L01+ radio
 100 uf capacitor
 2 10K resistors (for i2c)
 1N007 diode
 MI-SOL Rain Guage 
 SI7021 sensor

 Version history:
 02-10-2016 Initial version
*/

/**
   Configure MySensors
*/
// Enable debug prints
// #define MY_DEBUG

// Enable and select radio type attached
#define MY_RADIO_NRF24

/*
  Include libraries used by the sketch
*/
#include "ThresholdUtil.h"
#include <math.h>
#include <Time.h>
#include <SI7021.h>
#include <MySensors.h>

/**
   Define constants used by sketch
*/
#define BUCKET_PIN 3                  // The Arduino pin to which the bucket is attached. We need an interrupt pin (2 or 3 on the Uno and the Pro Mini) 
#define SKETCH_INFO "Outside weather" // The name of the sketch as presented to the gateway
#define SKETCH_VERSION "1.0"          // The version of the sketch as presented to the gateway
#define CHILD_ID_HUM  2               // The child id of the humidity sensor
#define CHILD_ID_TEMP 1               // The child id of the temperature sensor
#define CHILD_ID_RAIN_LOG 4           // The child id of the rain gauge
#define MS_WAIT 100                   // short delay used to give the NRF24L01+ antenna some time to recover from the last data sending
#define bucketSize 0.3                // I've used a MI-SOL Rain Guage which has a bucket size of 0.3 mm

/**
   Declare MySensors messages used by the node
*/
MyMessage msgHum( CHILD_ID_HUM, V_HUM );
MyMessage msgTemp( CHILD_ID_TEMP, V_TEMP );
MyMessage msgRain( CHILD_ID_RAIN_LOG, V_RAIN );
MyMessage lastCounterMsg( CHILD_ID_RAIN_LOG, V_VAR1 );

/**
   Declare variables used by the Sketch
*/
SI7021 humiditySensor; // Declare a SI7021 Temp humidity sensor object
float hwRainVolume = 0;           // Current rainvolume calculated in hardware.
unsigned long hwPulseCounter = 0; // Pulsecount recieved from GW
boolean pcReceived = false;       // If we have recieved the pulscount from GW or not
unsigned long lastTipTime = millis(); // TS of when the bucket tip has been detected for the last time
volatile unsigned long wasTippedCounter; // Queue for storing the tipped counter as been set by the interrupt handler.
byte lastHour;                    // Stores the hour used for checking if time needs to be synchronized

/**
  Present all child's to the gateway and query for the pulse count known by the HA controller.
*/
void presentation() {
  // Send the sketch version information to the gateway
  sendSketchInfo( SKETCH_INFO, SKETCH_VERSION );

  wait( MS_WAIT );
  // Register all sensors to gw (they will be created as child devices)
  present( CHILD_ID_HUM, S_HUM, "Outside temperature" );
  wait( MS_WAIT );
  present( CHILD_ID_TEMP, S_TEMP, "Outside humidity" );
  wait( MS_WAIT );
  present( CHILD_ID_RAIN_LOG, S_RAIN, "Rain fall" );
  wait( MS_WAIT );

  unsigned long functionTimeout = millis();
  while ( pcReceived == false && millis() - functionTimeout < 30000UL ) {
    request( CHILD_ID_RAIN_LOG, V_VAR1);
    Serial.println(F("Getting pulse count"));
    Serial.println(F("."));
    wait( 1000 );
  }
  attachInterrupt( digitalPinToInterrupt( BUCKET_PIN ), sensorTipped, LOW ); //FALLING );  // depending on location of the hall effect sensor may need CHANGE
}

/**
   Setup of the sketch. It initializes all sensors and queries the gateway for the current time.
*/
void setup() {
  Serial.begin( 115200 );
  pinMode( BUCKET_PIN, INPUT_PULLUP );

  humiditySensor.begin();

  registerThresholdedSensor( CHILD_ID_TEMP, 1, TEMPERATURE_SENSOR, 0.5, 30, 20 );
  registerThresholdedSensor( CHILD_ID_HUM, 2, HUMIDTY_SENSOR, 2.0, 30, 20 );

  unsigned long functionTimeout = millis();
  while ( timeStatus() == timeNotSet && millis() - functionTimeout < 30000UL ) {
    requestTime();
    Serial.println(F("Getting Time"));
    Serial.println(F("."));
    wait( 1000 );
  }

  lastHour = hour();
}

/**
  Sends the value of the rain gauge to the Gateway.
*/
void sendRainVolumeData() {
  float hwRainVolume = hwPulseCounter * bucketSize;
  Serial.print( "Tipped " );
  Serial.print( hwPulseCounter );
  Serial.println( " times." );
  Serial.print( "Rain fall is " );
  Serial.print( hwRainVolume, 1 );
  Serial.println( " mm." );
  send( msgRain.set( (float)hwRainVolume, 1 ) );
  wait( MS_WAIT );
  send( lastCounterMsg.set( hwPulseCounter ) );
  wait( MS_WAIT );
}

/**
  Main loop of the node. It checks:
  - whether the rain gauge bucket has been tipped.
  - whether the hourly heartbeat needs to be send.
  - checks all thresholded sensors
*/
void loop() {
  if ( wasTippedCounter != hwPulseCounter ) {
    hwPulseCounter = wasTippedCounter;
    sendRainVolumeData();
  }

  byte currentHour = hour();
  if (currentHour != lastHour) {
    Serial.println( "Resyncing hour" );
    requestTime(); // sync the time every hour
    wait( MS_WAIT );
    lastHour = currentHour;
    sendRainVolumeData(); // Send heart beat
  }

  checkThresholdedSensors( readTHSensor, updatedTHSensorValue );
}

/**
  Interrupt handler for handling bucket tips.
*/
void sensorTipped() {
  unsigned long thisTipTime = millis();
  if (thisTipTime - lastTipTime > 100UL) {
    wasTippedCounter++;
  }
  lastTipTime = thisTipTime;
}

/**
  Threshold util wants to know the current value of a specific sensor.
*/
void readTHSensor( uint8_t aSensorId, ThreshHoldedSensorType aType, float *value ) {
  si7021_env data = humiditySensor.getHumidityAndTemperature();
  switch ( aSensorId ) {
    case CHILD_ID_TEMP:
      *value = data.celsiusHundredths / 100.0;
      break;
    case CHILD_ID_HUM:
      *value = data.humidityPercent;
      break;
  }
}

/**
  Threshhold util detects that the value of a specific sensor needs to be send to the gateway.
*/
void updatedTHSensorValue( uint8_t child_id, uint8_t sensor_id, ThreshHoldedSensorType sensor_type, float value ) {
  switch ( child_id ) {
    case CHILD_ID_TEMP:
      Serial.print( "Sending temp " );
      Serial.println( value, 1 );
      send( msgTemp.set( value, 1 ) );
      wait( MS_WAIT );
      break;
    case CHILD_ID_HUM:
      Serial.print( "Sending Humidity " );
      Serial.println( value, 1 );
      send( msgHum.set( value, 1 ) );
      wait( MS_WAIT );
      break;
  }
}

/**
  Call back handler for handling time send by the gateway.
*/
void receiveTime(unsigned long time) {
  Serial.println( F("Time received..."));
  setTime(time);
  char theTime[6];
  sprintf(theTime, "%d:%2d", hour(), minute());
  Serial.println(theTime);
}

/**
  Callback handler for handling incomming MySensors message.
*/
void receive(const MyMessage &message) {
  if ( message.sensor == CHILD_ID_RAIN_LOG && message.type == V_VAR1) { // We only expect pulse count values from the gateway
    hwPulseCounter = message.getULong();
    wasTippedCounter = hwPulseCounter;
    pcReceived = true;

    Serial.print("Received last pulse count from gw: ");
    Serial.println(hwPulseCounter);
  }
}

ps. Because the old MySensors API's where removed from the main page, I had to move over to MySensors 2.0. I just uploaded the MySensors 2.0 to my serial gateway and everything seems to work fine. With this I mean all MySensors 1.5 node's are still doing their work. Love it!

EDITED: Added rain rate. But still testing.

[TheoL]

@AWI last question for today. Do you send the rain rate to domoticz as well? Still figuring out how to do this.

[sundberg84]

@TheoL - No I dont, and if i remember right its because i sleep the node I cant do the calculations.

[TheoL]

@sundberg84 I've added it. But so far Domoticz doesn't return a value whenever I query a JSON for the sensor. Maybe it does when the clock switches to the next hour.

[flopp]

@TheoL said:

@AWI last question for today. Do you send the rain rate to domoticz as well? Still figuring out how to do this.

Domoticz have some sort of rain rate, not like mm/12h, mm/6h but it will give mm/h depending how you send data to Domoticz it will be more or less correct.

[TheoL]

@flopp Thank you. What do you mean by sending data correctly? Do you have an example sketch?

[flopp]

@TheoL said:

@flopp Thank you. What do you mean by sending data correctly? Do you have an example sketch?

Not correctly, I wrote depending.

If you send data every 2 hours and ot every time the buck has tiped the rate will not be correct. Lets say you send/report every 2 hour, you report 10 mm, that means you have "collect" 10 mm for 2 hours. Maybe the hour was not raining, then the rate will show you 10mm/h, sorry if I confusing you.

What I mean is that you should send/report directly when the buck has tiped then the rate in DZ will be correct rate/h.

my sketch

#include <SPI.h>
#include <MySensor.h> 

// Running this in Domoticz stable version 2.5 will not work - upgrade to beta.

#define DIGITAL_INPUT_SENSOR 3 // The reed switch you attached. (Only 2 and 3 generates interrupt!)
#define INTERRUPT DIGITAL_INPUT_SENSOR-2 // Usually the interrupt = pin -2 (on uno/nano anyway)

#define CHILD_ID 1 // Id of the sensor child
#define BATT_CHILD 2
#define NODE_ID AUTO // or AUTO to let controller assign
#define SKETCH_NAME "Rain Gauge" // Change to a fancy name you like
#define SKETCH_VERSION "1.8" // Your version

unsigned long SLEEP_TIME = 180*60000; // Sleep time (in milliseconds).
//unsigned long SLEEP_TIME = 20000; // use this instead for debug

float hwRainVolume = 0; // Current rainvolume calculated in hardware.
int hwPulseCounter = 0; // Pulsecount recieved from GW
float fullCounter = 0; // Counts when to send counter
float bucketSize = 0.5; // Bucketsize mm, needs to be 1, 0.5, 0.25, 0.2 or 0.1
boolean pcReceived = false; // If we have recieved the pulscount from GW or not 
boolean reedState; // Current state the reedswitch is in
boolean oldReedState; // Old state (last state) of the reedswitch
unsigned long lastSend =0; // Time we last tried to fetch counter.

MySensor gw;
MyMessage volumeMsg(CHILD_ID,V_RAIN);
MyMessage lastCounterMsg(CHILD_ID,V_VAR1);
MyMessage battMsg(BATT_CHILD, V_VOLTAGE);

//=========================
// BATTERY VOLTAGE DIVIDER SETUP
// 1M, 470K divider across battery and using internal ADC ref of 1.1V
// Sense point is bypassed with 0.1 uF cap to reduce noise at that point
// ((1e6+470e3)/470e3)*1.1 = Vmax = 3.44 Volts
// 3.44/1023 = Volts per bit = 0.003363075
/*
#define VBAT_PER_BITS 0.003363075 
#define VMIN 1.9 // Vmin (radio Min Volt)=1.9V (564v)
#define VMAX 3.0 // Vmax = (2xAA bat)=3.0V (892v)
int batteryPcnt = 0; // Calc value for battery %
int batLoop = 0; // Loop to help calc average
int batArray[3]; // Array to store value for average calc.
int BATTERY_SENSE_PIN = A0; // select the input pin for the battery sense point
//=========================
*/

long result;
float batteryPcnt;
float batteryVolt;

void setup() 
{ 
pinMode(6,OUTPUT);
digitalWrite(6,HIGH);
// use the 1.1 V internal reference
//analogReference(INTERNAL); // For battery sensing

pinMode(DIGITAL_INPUT_SENSOR, INPUT_PULLUP); // sets the reed sensor digital pin as input

reedState = digitalRead(DIGITAL_INPUT_SENSOR); // Read what state the reedswitch is in
oldReedState = reedState; // Set startup position for reedswitch

delay(500); // Allow time for radio if power used as reset

//Begin (Change if you dont want static node_id! (NODE_ID to AUTO)
gw.begin(incomingMessage, NODE_ID, false);

// Send the Sketch Version Information to the Gateway
gw.sendSketchInfo(SKETCH_NAME, SKETCH_VERSION);

// Register this device as Rain sensor (will not show in Domoticz until first value arrives)
gw.present(CHILD_ID, S_RAIN); 
gw.present(BATT_CHILD, S_MULTIMETER);

Serial.println("Startup completed");
}

void loop() 
{ 

digitalWrite(6,HIGH);
delay(100);

gw.process();
//gw.begin(incomingMessage, NODE_ID, false);
unsigned long currentTime = millis();

//See if we have the counter/pulse from Domoticz - and ask for it if we dont.
if (!pcReceived && (currentTime - lastSend > 5000)) { 
gw.begin(incomingMessage, NODE_ID, false);
gw.request(CHILD_ID, V_VAR1);
Serial.println("Request pulsecount");
lastSend=currentTime;
gw.process();
return;
}
if (!pcReceived) {
return;
}

//Read if the bucket tipped over
reedState = digitalRead(DIGITAL_INPUT_SENSOR);
boolean tipped = oldReedState != reedState; 

//BUCKET TIPS!
if (tipped==true) {
gw.begin(incomingMessage, NODE_ID, false);
Serial.println("The bucket has tipped over...");
oldReedState = reedState;
hwRainVolume = hwRainVolume + bucketSize;
gw.send(volumeMsg.set((float)hwRainVolume,1));
gw.wait(1000);
fullCounter = fullCounter + bucketSize;

//Count so we send the counter for every 1mm
if(fullCounter >= 1){
hwPulseCounter++;
gw.send(lastCounterMsg.set(hwPulseCounter));
gw.wait(1000);
fullCounter = 0;
}
readVcc(); 
}

if (tipped==false) {

//No bucket tipped over last sleep-period, check battery then...
readVcc(); 
}

lastSend=currentTime;
Serial.println("sleep");
digitalWrite(6,LOW);
delay(1000);
gw.sleep(INTERRUPT, CHANGE, SLEEP_TIME); 
//The interupt can be CHANGE or FALLING depending on how you wired the hardware.
}

//Read if we have a incoming message.
void incomingMessage(const MyMessage &message) {
if (message.type==V_VAR1) {
hwPulseCounter = message.getULong();
hwRainVolume = hwPulseCounter;
pcReceived = true;
Serial.print("Received last pulse count from gw: ");
Serial.println(hwPulseCounter); 
}
}
/*
void batM() //The battery calculations
{
delay(500);
// Battery monitoring reading
int sensorValue = analogRead(BATTERY_SENSE_PIN); 
delay(500);

// Calculate the battery in %
float Vbat = sensorValue * VBAT_PER_BITS;
int batteryPcnt = static_cast<int>(((Vbat-VMIN)/(VMAX-VMIN))*100.);
Serial.print("Battery percent: "); Serial.print(batteryPcnt); Serial.println(" %"); 

// Add it to array so we get an average of 3 (3x20min)
batArray[batLoop] = batteryPcnt;

if (batLoop > 1) { 
batteryPcnt = (batArray[0] + batArray[1] + batArray[2]);
batteryPcnt = batteryPcnt / 3;

if (batteryPcnt > 100) {
batteryPcnt=100;
}

Serial.print("Battery Average (Send): "); Serial.print(batteryPcnt); Serial.println(" %");
gw.sendBatteryLevel(batteryPcnt);
batLoop = 0;

//Sends 1 per hour as a heartbeat.
gw.send(volumeMsg.set((float)hwRainVolume,1));
gw.send(lastCounterMsg.set(hwPulseCounter));
}
else 
{
batLoop++;
}
}
*/
long readVcc() {
Serial.println("readVcc");
// Read 1.1V reference against AVcc
ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
delay(2); // Wait for Vref to settle
ADCSRA |= _BV(ADSC); // Convert
while (bit_is_set(ADCSRA,ADSC));
result = ADCL;
result |= ADCH<<8;
result = 1126400L / result; // Back-calculate AVcc in mV
//return result;
gw.begin(incomingMessage, NODE_ID, false);
batteryPcnt = (result - 3300) * 0.111111;
batteryVolt = result/1000.000;
gw.sendBatteryLevel(batteryPcnt);
gw.send(battMsg.set(batteryVolt, 3));
/*Serial.print("battery volt:");
Serial.println(batteryVolt, 3);
Serial.print("battery percent:");
Serial.println(batteryPcnt);
*/
}

[TheoL]

@flopp Thank you for the explanation. I think I've got it.

I've added a RAINRATE msg like this
MyMessage rainRateMsg( CHILD_ID_RAIN_LOG, V_RAINRATE );

But I don't think domoticz uses it.

[TheoL]

@sundberg84 Using a real pulse counter instead of a 1mm pulse counter seems to work perfectly. Luckily it makes the sketch a bunch easier to implement and read. And there will also be no loss of 0.2 or 0.5 mm rain fall whenever you reset the node while it didn't have a .0 value.

[flopp]

@TheoL RAINRATE is implemented according to this page https://github.com/domoticz/domoticz/blob/master/hardware/MySensorsBase.cpp but I don't know how to use it. I know that DZ doesn't work with this example https://www.mysensors.org/build/rain

[flopp]

I have adjust my bucked to tip every ~0.25mm and calibrated it ofcourse

[AWI]

Domoticz just recently changed the method of rain rate calculation. It does not interpret rainrate values sent by sensors but calculates this by the total value coming in.

[TheoL]

@AWI Thank you again. I already had a gut feeling this would be the case. I'll strip out the rain rate code from the sketch.

[BulldogLowell]

@TheoL

Great to see this project continuing to grow legs!

[Hilltan]

This post is deleted!

[flopp]

@sundberg84 said:

I just wanted to celebrate 1 year for my Rainsensor on batteries, reporting every hour (or less when it rains). Still going strong and 81% battery left! Except for some range issues in the beginning you can see its working as it should:

WOW, nice. Would it be possible to see your Battery graph, if you have one?
I am send data every 2h or often when it rains but my battery is draining much quicker than yours. Maybe I will get 1 year out of it, so I am happy anyway.
But I am interested in your graph if the voltage is going down quicker in the beginning.

[Hilltan]

Maybe a stupid question, but it is possible to replace the SI7021 sensor with a DHT-22 sensor (the code has to be changed offsourse)? And get everything to work with ThresholdUtil? I have all parts, but not the SI7021 sensor to build the rain gauge.

[TheoL]

@Hilltan That should really be easy. I've created the threshold util especially for this. You only have to replace the si7021 init part with the DHT22 init part and replace the reading part of the si7021 in the threshold util callback with reading the DHT22 part. Then you're done.

Just give it a try yourself. It's really not that hard.

There's however a reason why I use the si7021 instead of the DHT's. I've had serious troubles with the DHT sensors. Some of them wouldn't report the values to the gateway for a week. After the that the node spontaneously started reporting again. I have a sense bender running for more than a half year flawlessly. So in my opinion the si7021 is superior to the DHT.

[AWI]

@Hilltan Like @TheoL mentioned, try to avoid the DHT22, especially for battery powered operation. The DHT-22 is (apart from other disadvantages) specified for a working voltage from 3.3-6V. And tend to get unstable at low voltages.