Read string from serial port and send it to gateway

Andreas Henriksson

Hello

I have play with my sensors a lot and it works perfect (only try standard sensors).
But now i want to create a sensor that read/write on the serial port (pin 0 and 1) and send it to the gateway
My C skills are very low but i try to learn :-)

This is my sketch:

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


#define CHILD_ID 0
String readString;

MySensor gw;
MyMessage msg(CHILD_ID,V_VAR1);

void setup()  
{ 
  gw.begin();
  Serial.begin(115200);

  // Send the sketch version information to the gateway and Controller
  gw.sendSketchInfo("test", "1.0");

  // Register all sensors to gateway (they will be created as child devices)
  gw.present(CHILD_ID, S_CUSTOM);
}

void loop()   
{
	
  while (Serial.available()) {
    delay(3);  //delay to allow buffer to fill 
    if (Serial.available() >0) {
      char c = Serial.read();  //gets one byte from serial buffer
      readString += c; //makes the string readString
    } 
  }

  if (readString.length() >0) {
      Serial.println(readString); //see what was received

	  gw.send(msg.set(readString));
	  readString="";
    
  } 
}

The string from serial port looks like this: "4. ERO 11421"

But when i verify the sketch in codebender i get this error:

Test_sensor.ino:69:16: error: no matching member function for call to 'set'
gw.send(msg.set(readString));
~~^

Any idea how to fix this

Thanks Andreas

TimO

According to:

https://github.com/mysensors/Arduino/blob/master/libraries/MySensors/MyMessage.cpp

There is no set method that accepts String type. You could use this one instead:

MyMessage& MyMessage::set(const char* value)

Greetings,
Tim

Andreas Henriksson

Thanks
Bu ti don't know how to fix this in my sketch :-( , can you please point me to the right direction ??

Andreas H

TimO

Hmmm, I'm out, when it comes to pure C, so I'm not sure if I'm really able to help you.

The first question that comes to my mind, when I read your sketch is: when does the loop end, that reads the characters?

If the string you receive ends for example with a newline, you could use something like: https://www.arduino.cc/en/Serial/ReadBytesUntil
where buffer is char[] and could be passed to msg.set().

Please keep in mind that the message content must not exceed 25 bytes.

Andreas Henriksson

Opps . i missed that in this sketch :-(

But the main problem is howto send a string och many chars :-(

fets

@Adreas Henriksson
I think that if you use String, you should call c_str() method to get char *.
Your have then to change the line with : gw.send(msg.set(readString.c_str()));
Hope this works.

Andreas Henriksson

Hello

I dont get any error when i compile, so i will make a test later today.

Thanks
Andreas H

Andreas Henriksson

This did the trick.
gw.send(msg.set(readString.c_str()));
Thanks for this :-)

Andreas H

eSumo

@Andreas-Henriksson
Hello. I need something like this ...
Can you show your functional version?
Thanks...

Andreas Henriksson

Hello, i don't using this any more but i found this on my laptop.
I can't confirm that i work, but it the latest version i have.

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

#define CHILD_ID_INFO 0
#define CHILD_ID_SOC 1
#define CHILD_ID_STATE 2
#define CHILD_ID_ERROR 3
#define CHILD_ID_SET_STATE 4
#define CHILD_ID_TEMP 5
#define CHILD_ID_HUM 6

//Pin
#define HUMIDITY_SENSOR_DIGITAL_PIN 3

MySensor gw;
MyMessage info(CHILD_ID_INFO, V_VAR1);
MyMessage soc(CHILD_ID_SOC, V_VAR2);
MyMessage state(CHILD_ID_STATE, V_VAR3);
MyMessage error(CHILD_ID_ERROR, V_VAR4);
MyMessage temp(CHILD_ID_TEMP, V_TEMP);
MyMessage hum(CHILD_ID_HUM, V_HUM);

DHT dht;

//DHT Sensor
const byte numChars = 25;
char receivedChars[numChars];
float lastTemp;
float lastHum;
boolean metric = true;

//MySensorr
int mySensorType;
int mySensorMsg;

String mySensorStr;
String mySensorRaw;

String mySensorRawSoc;
String mySensorStrSoc;

//Serial Read
boolean newData = false;

void setup()
{
  dht.setup(HUMIDITY_SENSOR_DIGITAL_PIN);

  gw.begin(incomingMessage, 1, false);
  Serial.begin(115200);

  // Send the sketch version information to the gateway and Controller
  gw.sendSketchInfo("Mover", "1.0");

  // Register all sensors to gateway (they will be created as child devices)
  gw.present(CHILD_ID_INFO, S_CUSTOM);
  gw.present(CHILD_ID_SOC, S_CUSTOM);
  gw.present(CHILD_ID_STATE, S_CUSTOM);
  gw.present(CHILD_ID_ERROR, S_CUSTOM);
  gw.present(CHILD_ID_SET_STATE, S_CUSTOM);
  gw.present(CHILD_ID_TEMP, S_TEMP);
  gw.present(CHILD_ID_HUM, S_HUM);

  metric = gw.getConfig().isMetric;
}

void loop()
{
  recvWithStartEndMarkers();
  showNewData();
  gw.process();

}

void incomingMessage(const MyMessage &message)
{
  // We only expect one type of message from controller. But we better check anyway.
  if (message.type == 28)
  {
    if (message.getInt() == 99)
    {
      float temperature = dht.getTemperature();
      //if (isnan(temperature))
      //{
      //  Serial.println("Failed reading temperature from DHT");
      //}
      
      if (temperature != lastTemp)
      {
        lastTemp = temperature;
        if (!metric)
        {
          temperature = dht.toFahrenheit(temperature);
        }
        
        //Serial.print("T: ");
        //Serial.println(temperature);
      }
      gw.send(temp.set(temperature, 1));

      float humidity = dht.getHumidity();
      //if (isnan(humidity))
      //{
      //  Serial.println("Failed reading humidity from DHT");
      //}
      if (humidity != lastHum)
      {
        lastHum = humidity;
        
        //Serial.print("H: ");
        //Serial.println(humidity);
      }
      gw.send(hum.set(humidity, 1));


    }
    else {
      //Serial.println(message.type);
      //Serial.print("Incoming change for sensor:");
      //Serial.println(message.sensor);
      //Serial.print(", New status: ");
      Serial.print(message.getInt());
    }  
  }


  //}
}

void recvWithStartEndMarkers()
{
  static boolean recvInProgress = false;
  static byte ndx = 0;
  char startMarker = '<';
  char endMarker = '>';
  char rc;

  // if (Serial.available() > 0) {
  while (Serial.available() > 0 && newData == false)
  {
    rc = Serial.read();

    if (recvInProgress == true)
    {
      if (rc != endMarker)
      {
        receivedChars[ndx] = rc;
        ndx++;
        if (ndx >= numChars)
        {
          ndx = numChars - 1;
        }

      }
      else
      {
        receivedChars[ndx] = '\0'; // terminate the string
        recvInProgress = false;
        ndx = 0;
        newData = true;
      }
    }

    else if (rc == startMarker)
    {
      recvInProgress = true;
    }
  }
}

void showNewData()
{
  if (newData == true)
  {
    mySensorRawSoc = receivedChars;
    mySensorStrSoc = mySensorRawSoc.substring(2, 6);

    mySensorRaw = receivedChars;
    mySensorStr = mySensorRaw.substring(2);

    switch (receivedChars[0])
    {

      case '1':
        gw.send(info.set(mySensorStr.c_str()));
        break;
      case '2':
        gw.send(soc.set(mySensorStrSoc.c_str()));
        break;
      case '3':
        gw.send(state.set(mySensorStr.c_str()));
        break;
      case '4':
        gw.send(error.set(mySensorStr.c_str()));
        break;
    }

    /*Serial.print ("type: ");
    Serial.println (receivedChars[0]);
    Serial.print ("Msg: ");
    Serial.println (receivedChars[2]);
    Serial.println (mySensorRaw);
    Serial.println (mySensorStr);
    */
    mySensorRawSoc = "";
    mySensorStrSoc = "";
    mySensorRaw = "";
    mySensorStr = "";

    newData = false;
  }
}

eSumo

OK. Thanks. I try...

Read string from serial port and send it to gateway

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