Getting Data

FAQ
1

Hi, I need some help. Look my code

#define BLYNK_PRINT Serial
#include <SPI.h>
#include <Ethernet.h>
#include <BlynkSimpleEthernet.h>
#include <BlynkEthernet.h>
#include <dht.h>
#define dht_dpin A1 
dht DHT;
char auth[] = "b52126f2528748b38d6dd65b30d22762";

void setup()
{
  Serial.begin(9600);
  Blynk.begin(auth);
  DHT.read11(dht_dpin); //read the informations
}
BLYNK_WRITE (1){
   Blynk.virtualWrite(DHT.temperature,millis()/1000); 

}
void loop()
{
  
  Blynk.run();
}

I didn’t understand very well how to send data from Arduino to Blynk. Could you, guys, explain me how i can do this? What’s wrong in my code?
thanks

2

Hi Daniel,

Have you looked at the examples in the library? There is an example written specifically for your needs.

 **************************************************************
 * This example shows how value can be pushed from Arduino to
 * the Blynk App.
 *
 * For this example you'll need SimpleTimer library:
 *   https://github.com/jfturcot/SimpleTimer
 * Visit this page for more information:
 *   http://playground.arduino.cc/Code/SimpleTimer
 *
 * App dashboard setup:
 *   Value Display widget attached to V5
 *
 **************************************************************/

#define BLYNK_PRINT Serial    // Comment this out to disable prints and save space
#include <SPI.h>
#include <Ethernet.h>
#include <BlynkSimpleEthernet.h>
#include <SimpleTimer.h>

// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "YourAuthToken";

SimpleTimer timer;

void setup()
{
  Serial.begin(9600); // See the connection status in Serial Monitor
  Blynk.begin(auth);

  // Setup function to be called each 1000 milliseconds
  timer.setInterval(1000, sendUptime);
}

// This function sends Arduino's up time every second to Virtual Pin (5).
// In the app, Widget's reading frequency should be set to PUSH. This means
// that you define how often to send data to Blynk App.
void sendUptime()
{
  // You can send any value at any time.
  // Please don't send more that 10 values per second.
  Blynk.virtualWrite(5, millis()/1000);
}

void loop()
{
  Blynk.run(); // Initiates Blynk
  timer.run(); // Initiates SimpleTimer
}

Please read all the instructions carefully and I hope you’ll succeed. Don’t forget to install SimpleTimer library.

3 
blynk.cpp.o: In function `setup':
C:\Program Files (x86)\Arduino/blynk.ino:54: undefined reference to `SimpleTimer::setInterval(long, void (*)())'
blynk.cpp.o: In function `loop':
C:\Users\Daniel\Documents\Arduino\libraries\blynk-library-0.2.1/Blynk/BlynkProtocol.h:155: undefined reference to `SimpleTimer::run()'
blynk.cpp.o: In function `__static_initialization_and_destruction_0':
C:\Program Files (x86)\Arduino/blynk.ino:40: undefined reference to `SimpleTimer::SimpleTimer()'
collect2.exe: error: ld returned 1 exit status

Appers this error.Do you have any ideia how to solution that?

4

Do you have any ideia how to solution that?

Look like you didn’t install SimpleTimer library.

5

Daniel, sorry for pointing that out, but what’s the point of asking questions and not reading the replies then?

Everyone is trying to help you, but come on, time is precious! :wink:

6

Sorry about that, I found my mistake. I’ll pay more attention in my questions, really sorry guys

7

I too am having trouble with this project. I too uploaded Pavel’s code from above and added my auth key, but don’t know how to setup the app to receive the data that is being sent every 3000 ms. I want to go through these exercises to learn how to retrieve data collected by a DHT22 on Arduino Mega with Ethernet. There only seems to be fragmented info in this forum. I also stumbled onto an Instructable that involved a DHT, Arduino and ESPXXXX (wifi?), but was unable to make sense of it. My code skills are rough, and I believe I need more info than what I have been able to find thus far.

Can someone help either with code, app setup and/or explanations?