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How to control a relay device (Devolo or Sonoff) per Blynk using IFTT?


#1

Hello all,

I need your help.

I will use a motion detector connected to a Wemos D1 Mini (ESP8622) to control a relay device (Devolo or Sonoff).
To bridge blynk to Devolo or Sonoff, I would like to use IFTT with Webhooks.

Here’s the code. Instead an DHT11, a motion detector will be installed.

   /***slo-slo-nodemcu09
07.2016***/

#define BLYNK_PRINT Serial    // Comment this out to disable prints and save space
#include <SPI.h>
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <SimpleTimer.h>
#include <DHT.h>

char auth[] = "dein Blynk Auth Token";
char ssid[] = "dein WLAN-Name";
char pass[] = "dein WLAN-Passwort";

#define DHTPIN 2          // What digital pin we're connected to, d.h. D4 in NodeMCU

// 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);
SimpleTimer 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()
{
  int h = dht.readHumidity();
  int t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit

  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }
  // 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()
{
  Serial.begin(9600); // See the connection status in Serial Monitor
  Blynk.begin(auth, ssid, pass);

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

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


So, my question is:
What do I have to do in IFTT, to tell the relay device to power on, if the motion detector changes from 0 to 1 in Blynk?

Best regards
Norman


#2

The simplest way is to forget IFTTT and the stock Sonoff Ewelink firmware and simply upload your own code Blynk code to the Sonoff.
You could then use Blynk Bridge to send instructions from your Wemos to the Sonoff.

Pete.


#3

I want to hold on the Ewelink firmware, because it is much more comfortable to connect the Sonoff to Amazon Alexa than with Blynk firmware.

My project is, to use the motion detector with ESP8622 to send a signal to a Sonoff switchable Power Outlet.
I think, I can use a analog input on the ESP8622, but I don’t know how to config the IFTTT Bridge :slightly_frowning_face:

Norman


#4

Why, when you’re checking for a binary change from 0 to 1?

What you’re asking for with IFTTT is for the IFTTT system to monitor the Blynk server for a change in value on the Blynk server. This would mean polling the Blynk server on a frequent basis (at least once per second if you’re looking for a fairly responsive system). I don’t think that’s possible, and certainly doesn’t sound very desirable.

Pete.