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Unable to receive data from virtual pin, showing %3f


#1

Hi,

I am a new user of blynk.

I have make a simple project to read Temperature and humidity.
The code is Ok, as I can read the value in the monitor.
But in the app on my smartphone, I never receive the value.
The connection is good.
I have put a switch to test with the led, and it’s OK
I have 2 virtuals pin (5 & 6)
I use 2 labeled Value
Select the correct virtual pin for each
put the value “Temp: /pin/ °C” and “Humid: /pin/ °C”
And Push mode.
If I start, I can read Temp: %3f °C and Humid: %3f °C

What is wrong?


/*************************************************************
  Download latest Blynk library here:
    https://github.com/blynkkk/blynk-library/releases/latest

  Blynk is a platform with iOS and Android apps to control
  Arduino, Raspberry Pi and the likes over the Internet.
  You can easily build graphic interfaces for all your
  projects by simply dragging and dropping widgets.

    Downloads, docs, tutorials: http://www.blynk.cc
    Sketch generator:           http://examples.blynk.cc
    Blynk community:            http://community.blynk.cc
    Follow us:                  http://www.fb.com/blynkapp
                                http://twitter.com/blynk_app

  Blynk library is licensed under MIT license
  This example code is in public domain.

 *************************************************************

  This example shows how value can be pushed from Arduino to
  the Blynk App.

  WARNING :
  For this example you'll need Adafruit DHT sensor libraries:
    https://github.com/adafruit/Adafruit_Sensor
    https://github.com/adafruit/DHT-sensor-library

  App project setup:
    Value Display widget attached to V5
    Value Display widget attached to V6
 *************************************************************/

/* Comment this out to disable prints and save space */
#define BLYNK_PRINT Serial


#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <DHT.h>
#include <SPI.h>


// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "3c873a1092d44f068b34ab33e02f4363";

// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "virus.exe";
char pass[] = "olivierlegros";

#define DHTPIN 5          // What digital pin we're connected to

// Uncomment whatever type you're using!
#define DHTTYPE DHT11     // DHT 11
//#define DHTTYPE DHT22   // DHT 22, AM2302, AM2321
//#define DHTTYPE DHT21   // DHT 21, AM2301

DHT dht(DHTPIN, DHTTYPE);
BlynkTimer timer;

// 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 sendSensor()
{

  float h = dht.readHumidity();
  float t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit

  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }
  else {
    Serial.print("Humidity: ");
    Serial.print(h);
    Serial.print(" %\t");
    Serial.print("Temperature: ");
    Serial.print(t);
    Serial.println(" *C ");
  }
  // You can send any value at any time.
  // Please don't send more that 10 values per second.
  Blynk.virtualWrite(V5,h);
  Blynk.virtualWrite(V6,t);

}

void setup()
{
  // Debug console
  Serial.begin(9600);

  Blynk.begin(auth, ssid, pass);
  // You can also specify server:
  //Blynk.begin(auth, ssid, pass, "blynk-cloud.com", 80);
  //Blynk.begin(auth, ssid, pass, IPAddress(192,168,1,100), 8080);

  dht.begin();

  // Setup a function to be called every second
  timer.setInterval(1000L, sendSensor);
}

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

Thanks for your help


#2

Did you look for “%3f” at this forum?


#3

I have the exact same problem…


#4

Searching this forum would have shown that recent changes require the latest ESP Arduino core 2.4.1


closed #5