NodeMCU keeps going offline

Solved
1

Before creating the topic

  1. Search forum for similar topics
    I tried the BlynkTimer did not worked and also i tried without any timesrs or delays, still same issue
  2. Check http://docs.blynk.cc and http://help.blynk.cc/
  3. Add details :
    • Hardware model + communication type. NodeMCU v3 - wifi
    • Smartphone OS (iOS or Android) + version: Latest android version
    • Blynk server or local server - Local server
    • Blynk Library version 0.6.1
    • Add your sketch code.

#define BLYNK_PRINT Serial

#include "DHT.h"                              // DHT Sensor
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>

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

#define SensorPin A0

IPAddress local_IP(192, 168, 88, 8);
IPAddress gateway(192, 168, 88, 1);

IPAddress subnet(255, 255, 255, 0);
IPAddress primaryDNS(8, 8, 8, 8);
IPAddress secondaryDNS(8, 8, 4, 4);

DHT dht(5, DHT21);
BlynkTimer timer;

void notifySoil(float prt, String type)
{
  if (prt < 52.00 && type == "soil") {
    Blynk.notify("Alert Soil Hum low: " + String(prt) + "%");
  };
  if (prt > 27.00 && type == "temp") {
    Blynk.notify("Alert Temp high: " + String(prt) + "C");
  };
   if (prt < 21.00 && type == "temp") {
    Blynk.notify("Alert Temp low: " + String(prt) + "C");
  };
}

void climateRoutine() {
    int dryValue = 1023;
    int wetValue = 0;
    int friendlyDryValue = 0;
    int friendlyWetValue = 100;
    float percentage = 0.0;
    byte h1 = dht.readHumidity();        
    byte t1 = dht.readTemperature();
    float sensorValue = analogRead(SensorPin);
    percentage = map(sensorValue, dryValue, wetValue, friendlyDryValue, friendlyWetValue);
    Blynk.virtualWrite(V0, t1);
    Blynk.virtualWrite(V1, h1);
    Blynk.virtualWrite(V2, percentage);
    notifySoil(percentage, "soil");
    notifySoil(t1, "temp");
    Serial.println(t1);
    }

void setup() {
  Serial.begin(9600);
  if (!WiFi.config(local_IP, gateway, subnet, primaryDNS, secondaryDNS)) {
     Serial.println("STA Failed to configure");
  };
  Blynk.begin(auth, ssid, pass, IPAddress(192,168,88,7), 8080);
  dht.begin();
  timer.setInterval(40000L, climateRoutine);
}


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

Initially i was using the public server, and then i moved to a local one, I thought maybe my devboard would make to many requests or something adn I wanted to see the logs.

Did not found anything relevant in the logs.

Then i found some forum posts about not using delay in the code, so i tried using BlynkTimer, but same issues persisted.

Then i eliminated all trimmers or delays and still the same issue.

Can’t find anything else on the forum or google…

I am new to c and maybe i am doing something wroang in the code, idk…

2

Your code is structured so that every cycle of the void loop you try to do multiple Blynk.writes and also potentially send multiple Blynk notifications.
This doesn’t work!

Using a timer to call your climateRoutine function, maybe once every 10 seconds is the solution, plus you should use flags to indicate that a notification has been sent when your alert criteria have been met so that you don’t then keep re-sending the same notification. You would then clear the flag when the criteria is no longer met, to enable future alerts to be sent.

You should read this:

and if your use of a timer doesn’t work then post your revised code along with an explanation of what is and isn’t working.

Pete.

3

Thanks for the answer,
I already cleaned the code.
Also, thanks for the tag pointers, for the notifications.

Now that i have defined #define BLYNK_PRINT Serial, I am seeing the following in the console:

[526787] Connecting to 192.168.88.7
[531788] Connecting to 192.168.88.7
[536789] Connecting to 192.168.88.7
[541790] Connecting to 192.168.88.7
[546791] Connecting to 192.168.88.7
[546796] Ready (ping: 2ms).
255
[575867] Heartbeat timeout
[577870] Connecting to 192.168.88.7
[582871] Connecting to 192.168.88.7
[587872] Connecting to 192.168.88.7
[592873] Connecting to 192.168.88.7
[597874] Connecting to 192.168.88.7
[602875] Connecting to 192.168.88.7
255
[607876] Connecting to 192.168.88.7

I don’t think this is normal, because it still behaves really strange, the value do not get updated in the adnroid app, the servers goes down, but when i click on it says it is up, and so on.

Same thing with cloud:

   / _ )/ /_ _____  / /__
  / _  / / // / _ \/  '_/
 /____/_/\_, /_//_/_/\_\
        /___/ v0.6.0 on NodeMCU

[4485] Connecting to blynk-cloud.com:80
[4654] Ready (ping: 37ms).
255
[53759] Heartbeat timeout
[55778] Connecting to blynk-cloud.com:80
[60779] Connecting to blynk-cloud.com:80
[65780] Connecting to blynk-cloud.com:80
[70781] Connecting to blynk-cloud.com:80
[75782] Connecting to blynk-cloud.com:80
[80783] Connecting to blynk-cloud.com:80
255
4

Is this the t1 value?

Pete.

5

Yes.

I found my issue, apparently if I put the included files in this order:

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

I do not have an issue anymore.

Who knew, the order was so important :slight_smile: