Blynk.logEvent sending alerts

Need Help With My Project
1

I want to stop sending alerts when it’s over 70 and I tried this code.
Did I miss something?
Code :

void alert(){
    if (dht.readHumidity() < 70);{
    Blynk.logEvent("moisalert", "Humidity Low");
    Serial.println("Humidity Low");
}
}
2

More information required.

Pete.

1 Like
3

when the humidity over 70% it still send alert to me

#define BLYNK_TEMPLATE_ID "TMPL1ZBP7FMf"
#define BLYNK_DEVICE_NAME "MUSHROOM"
#define BLYNK_AUTH_TOKEN "***************"

#define BLYNK_PRINT Serial


#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <DHT.h>
#include <DHT_U.h>
#include <SimpleTimer.h>

char auth[] = BLYNK_AUTH_TOKEN;
char ssid[] = "********";
char pass[] = "********";

#define DHTPIN D2
#define DHTTYPE DHT11
#define relay D1

DHT dht(DHTPIN, DHTTYPE);
SimpleTimer timer;


void sendSensor()
{
  float h = dht.readHumidity();
  float t = dht.readTemperature();

  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }
  Blynk.virtualWrite(V5, h);
  Blynk.virtualWrite(V6, t);
  Serial.println(dht.readHumidity());;
}

void setup()
{
  // Debug console
  Serial.begin(9600);
  Blynk.begin(auth, ssid, pass);
  dht.begin();
  timer.setInterval(1000L, sendSensor);
  timer.setInterval(60000L, alert);
  pinMode(relay, OUTPUT);
}

void loop()
{
  Blynk.run();
  timer.run();
}
BLYNK_WRITE(V1)
{
  int button = param.asInt();
  
  if (button == 1){
   digitalWrite(relay, HIGH);
   Serial.println(button);
  }
  else if (button == 0){
    digitalWrite(relay, LOW);
    Serial.println(button);
  }
}


void alert(){
    if (dht.readHumidity() < 70);{
    Blynk.logEvent("moisalert", "Humidity Low");
    Serial.println("Humidity Low");
}
}
4

What does your serial monitor show?

Pete.

5

123
1231920×1080 45.8 KB

6

312eqw
312eqw1920×1080 68.7 KB
qweqw
qweqw1920×1080 79.8 KB

7

It would help if you took one reading, and stored this in a global variable, then used this reading whenever you are printing out the humidity and doing any if comparisons.

On another note, there is a limit of 100 events (and therefore a maximum of 100 notifications) per 24 hour period.
Your current process could use up all of that allocation in 100 minutes.

Also, please copy/paste serial output, and use triple backticks at the beginning and end, rather than posting screenshots.

Pete.

8

Thanks !I will try it

9

Your printout says your HUM is “70.00”.
I’d say that any value in the range [69.995 - 70.005] would be printed as 70.00.

From this, i’d say your comparison “<70” could easily evaluate to TRUE for a HUM value of 69.995, but be printed as 70.00. (and you also print and compare from different readings)

// I don’t know the resolution of your humidity sensor, but dealing with float values often means you can have values like 70.00001, etc.

Try to evaluate with “<70.00” instead.

And - take the hum reading in the alert() function and print THIS value to the serial AND compare with this same reading (not 2 different readings.)