setInterval ? conflict?

In my project, I have a temperature sensor and a push button to control an LED
The problem, when the temperature is sent every 5 seconds, I cannot turn on the led.
Looks like the two functions are in conflict, how to avoid this problem?

  timer.setInterval(100L, checkPhysicalButton);
  timer.setInterval(5000L, sendTemps);    

Impossible to say from two lines of code.


#define BLYNK_PRINT Serial

#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>

#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

#include <OneWire.h>
#include <DallasTemperature.h> 
#define ONE_WIRE_BUS 23          // Your ESP8266 pin (ESP8266 GPIO 2 = WeMos D1 Mini pin D4)
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

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

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

// Set your LED and physical button pins here
const int ledPin = 18;
const int btnPin = 19;

BlynkTimer timer;

void checkPhysicalButton();

int ledState = LOW;
int btnState = HIGH;

// Every time we connect to the cloud...
  // Request the latest state from the server

  // Alternatively, you could override server state using:
  //Blynk.virtualWrite(V2, ledState);

// When App button is pushed - switch the state
  ledState = param.asInt();
  digitalWrite(ledPin, ledState);

void checkPhysicalButton()
  if (digitalRead(btnPin) == LOW) {
    // btnState is used to avoid sequential toggles
    if (btnState != LOW) {

      // Toggle LED state
      ledState = !ledState;
      digitalWrite(ledPin, ledState);

      // Update Button Widget
      Blynk.virtualWrite(V2, ledState);
    btnState = LOW;
  } else {
    btnState = HIGH;

float roomTemperature;            // Room temperature in F

#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)

#define NUMFLAKES     10 // Number of snowflakes in the animation example

#define LOGO_HEIGHT   16
#define LOGO_WIDTH    16
static const unsigned char PROGMEM logo_bmp[] =
{ B00000000, B11000000,
  B00000001, B11000000,
  B00000001, B11000000,
  B00000011, B11100000,
  B11110011, B11100000,
  B11111110, B11111000,
  B01111110, B11111111,
  B00110011, B10011111,
  B00011111, B11111100,
  B00001101, B01110000,
  B00011011, B10100000,
  B00111111, B11100000,
  B00111111, B11110000,
  B01111100, B11110000,
  B01110000, B01110000,
  B00000000, B00110000 };

void setup()
  // Debug console

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

  pinMode(ledPin, OUTPUT);
  pinMode(btnPin, INPUT_PULLUP);
  digitalWrite(ledPin, ledState);

  sensors.begin();                        // Starts the DS18B20 sensor(s).
  sensors.setResolution(10);              // More on resolution:

 if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { 
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever

  // Show initial display buffer contents on the screen --
  // the library initializes this with an Adafruit splash screen.
  delay(2000); // Pause for 2 seconds

  // Clear the buffer

  // Show the display buffer on the screen. You MUST call display() after
  // drawing commands to make them visible on screen!
  // display.display() is NOT necessary after every single drawing command,
  // unless that's what you want...rather, you can batch up a bunch of
  // drawing operations and then update the screen all at once by calling
  // display.display(). These examples demonstrate both approaches...

  // Invert and restore display, pausing in-between
  timer.setInterval(100L, checkPhysicalButton);
  timer.setInterval(9000L, sendTemps);    

void loop()
  // You can inject your own code or combine it with other sketches.
  // Check other examples on how to communicate with Blynk. Remember
  // to avoid delay() function!
void sendTemps()
  sensors.requestTemperatures();                  // Polls the sensors.
  roomTemperature = sensors.getTempCByIndex(0);   // Stores temperature. Change to getTempCByIndex(0) for celcius.
  Blynk.virtualWrite(1, roomTemperature);         // Send temperature to Blynk app virtual pin 1.


  display.setTextSize(2); // Draw 2X-scale text
  display.setCursor(10, 0);
  display.println(F("Salon :"));
  display.display();      // Show initial text

   display.setTextSize(1);             // Draw 2X-scale text


Don’t use delays with Blynk :stuck_out_tongue_winking_eye:

and you have to stage timers

because 9000 = 90*100

so at 9000, you have sendTemps and checkPhysicalButton execution at same time

try :
timer.setInterval(100L, checkPhysicalButton);
timer.setInterval(9030L, sendTemps);

If you mean that whist the sendTemps function is executing the physical button is unresponsive for 1.1 seconds then this is due to the two blocking delays at the end of the sendTemps function.

If you mean something else, it would be useful if you’d explain in more detail what your issue is.


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you understood my problem very well @PeteKnight

Thank you @Blynk_Coeur I removed the delay, it works perfectly

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