Data transfer speed is too slow

Hello to everyone,

I use Arduino UNO and ESP8266-01 in my project. I’ve been observing the system for about three days. The problems I encounter are;

1- Wifi module is experiencing disconnections.

2- Data transfer between BLYNK and arduino is very slow. I can’t follow the graphical snapshots.

3- The data read by Arduino Nun is updated too late in the application

I’m adding the code below and a few screenshots so you can have ideas.

I would appreciate it if you would share your expensive experience and opinions with me. Thank you to all concerned

#define BLYNK_PRINT Serial

#include <ESP8266_Lib.h>
#include <BlynkSimpleShieldEsp8266.h>
#include "Adafruit_CCS811.h"
#include <DHT.h>

char auth[] = "3ebxxxxxcae41xxxxxx6";
char ssid[] = "xxx";
char pass[] = "xxxx";

#include <SoftwareSerial.h>
SoftwareSerial EspSerial(2, 3); // RX, TX

#define ESP8266_BAUD 9600
ESP8266 wifi(&EspSerial);

#define DHTPIN 4
#define DHTTYPE DHT22

Adafruit_CCS811 ccs;
BlynkTimer timer;

   int c = ccs.geteCO2();
   float n = dht.readHumidity();
   float s = dht.readTemperature();

   int sicaklikset;
   int nemset;
   int co2set;

  // Request Blynk server to re-send latest values for all pins

  // You can also update individual virtual pins like this:
  //Blynk.syncVirtual(V0, V2);

  // Let's write your hardware uptime to Virtual Pin 6
  int value = millis() / 1000;
  Blynk.virtualWrite(V6, value);

  // You'll get uptime value here as result of syncAll()
  int sicaklikset = param.asInt();
  // You'll get uptime value here as result of syncAll()
  int nemset = param.asInt();
  // You'll get uptime value here as result of syncAll()
  int co2set = param.asInt();

void sendSensor()

   int c = ccs.geteCO2();
   float n = dht.readHumidity();
   float s = dht.readTemperature();

      Blynk.virtualWrite(V0, s);
      Blynk.virtualWrite(V1, n);
      Blynk.virtualWrite(V2, c);

void setup() {


   Blynk.begin(auth, wifi, ssid, pass);

  timer.setInterval(1000L, sendSensor);

void loop() {

Even with what looks like a fairly good ping, I suspect it all comes down to your network… The WiFi, Router, Internet… perhaps even your phone??

I am running multiple Arduino/ESP-01 combos in a very congested WiFi area (including on my own network) and getting very good responses even from heavy or fast responding tasks. However I am also using a Local Server, so that helps.

I’m a rookie. How to install local server for use my esp

It’s all in here :wink:

Hint - 4th one in the list (at time of this post)

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BTW, how are you determining this “slow” speed anyhow?? You are reading sensors once per second… so, it is like taking many seconds, minutes, hours, days… to show on your App??

It’s also worth noting that with Superchart, the minimum granularity is 1 minute, so the readings taken every 5 seconds will be averaged out and allocated to the record for that minute.

More info at the end of this section of the documentation:


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like that

Sir may u share example code while esp connect to loca server pls?

The connection to local server is very similar to connecting to cloud server - just specifying the IP address and port of the local server instead of in your blynk.begin command.

You’ve shared a screenshot of one of your gauges, but this doesn’t answer the question that @Gunner asked - what makes you think that the updates to the gauges in the app are slow?
I’d suggest that you add some Serial.print commands into your sendSensor function to print the values to your serial monitor and see what the delay is between the values appearing there and in the app.


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You should be setting the refresh interval to PUSH when using virtual pins.

The only difference would be in the Blynk.begin() command… so not much to show that will do you any good… besides it is all in the documentation and the examples…

Blynk.begin(auth, wifi, ssid, pass);
  // You can also specify server:
  //Blynk.begin(auth, wifi, ssid, pass, "", 80);
  //Blynk.begin(auth, wifi, ssid, pass, IPAddress(xxx,xxx,xxx,xxx), 8080);

like that?

lynk.begin(auth, wifi, ssid, pass, IPAddress(, 8080);

Your screenshots tell me nothing.

Did you install a Local Server on something?? Is it configured? did you read all the directions? if you need to ask, then probably not :wink:

Besided, you had setup your display widgets incorrectly… so that is probably your whole issue there.

Change them all to PUSH and see what happens.

I did it but it has got same problem. :confused:

I still don’t understand what the “problem” is… how are you determining this “slow” issue??

Although I interfere with DHT22, the data is the same as before. The actual data is written to the application screen after a very long interval

Well… I am going to ignore this topic for a “very long interval” if that is all the vague details you have :stuck_out_tongue:

Even the DHT22 is not that quick of a sensor… change your readings to every 5 seconds and monitor it.

Also, try something more instantaneous like a Button or Slider widget controlling an LED or something.

Blynk has a built in heartbeat monitor, so if your data connection was “bad” then you should be seeing disconnection notices all the time.

I think My problem is connection. I should connect to local host.
And I’m sorry for bad english and understanding.

Thanks @Gunner problem is “1 sec” :slight_smile: I’m sorry for your trouble. :pray: thank u so much :pray: :pray:

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