Oled not displaying everytime i upload blynk code

[marksds]

#define BLYNK_TEMPLATE_NAME "Voltage sensor"
#define BLYNK_TEMPLATE_ID "TMPL6VbgjbzCM"
#define BLYNK_AUTH_TOKEN "ifBiQP3zJjkBqhgTR7QyLpauvG3w-NAG"

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

// setup OLED display
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET 4
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

//current
int sensorIn = 27;      // pin where the OUT pin from sensor is connected on Arduino
int mVperAmp = 185;           // this the 5A version of the ACS712 -use 100 for 20A Module and 66 for 30A Module
int Watt = 0;
double Voltage = 0;
double VRMS = 0;
double AmpsRMS = 0;

//voltage
int voltage_offset = 20;

//piezo
int sensorOutput = 26; //piezo
int ledPin = 34; // pin connected to LED
int threshold = 100;

BlynkTimer timer;

char ssid[] = "Hulaanmo"; // Your WiFi SSID
char pass[] = "Hulaanmo"; // Your WiFi password

float getVPP()
{
  float result;
  int readValue;                // value read from the sensor
  int maxValue = 0;             // store max value here
  int minValue = 4096;          // store min value here ESP32 ADC resolution
  
  uint32_t start_time = millis();
  while((millis()-start_time) < 1000) //sample for 1 Sec
  {
      readValue = analogRead(sensorIn);
      // see if you have a new maxValue
      if (readValue > maxValue) 
      {
          /*record the maximum sensor value*/
          maxValue = readValue;
      }
      if (readValue < minValue) 
      {
          /*record the minimum sensor value*/
          minValue = readValue;
      }
  }
   
  // Subtract min from max
  result = ((maxValue - minValue) * 3.3)/4096.0; //ESP32 ADC resolution 4096
      
  return result;
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

  pinMode(ledPin, OUTPUT); // declare led connected pin as output
  pinMode(sensorOutput, INPUT_PULLDOWN); // enable internal pull-down resistor

  // Initialize OLED display
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.clearDisplay();
  display.display();

  // Connect to WiFi
  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
  Serial.println("Initializing Blynk...");

  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);

  // Setup Blynk timer
  timer.setInterval(1000L, sendSensorData);
}

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

void sendSensorData() {
  int volt = analogRead(14);// read the input - GPIO_NUM_34
  double voltage = map(volt,0, 4096, 0, 1650) + voltage_offset;

  voltage /= 100; // divide by 100 to get the decimal values
  Serial.print("Voltage: ");
  Serial.print(voltage);
  Serial.println("V");

  delay(500);

  int sensorValue = 0; // default value when no sensor is connected
  sensorValue = analogRead(sensorOutput); // read analog voltage from sensor
  delay(10); // debounce the sensor input

  // Calculate the voltage based on the analog reading
  float voltagePiezo = sensorValue * (5.0 / 1023.0);

  Serial.print(" | Voltage: ");
  Serial.print(voltagePiezo);
  Serial.println(" V");

  if (sensorValue >= threshold) { // check voltage level from sensor
    digitalWrite(ledPin, HIGH);
    Serial.println("LED is ON");
  } else {
    digitalWrite(ledPin, LOW);
    Serial.println("LED is OFF");
  }
  delay(500); // wait 500ms before taking the next reading

  Voltage = getVPP();
  VRMS = (Voltage/2.0) *0.707;   //root
    AmpsRMS = ((VRMS * 1000)/mVperAmp)-0.13;
  Serial.print(AmpsRMS);
  Serial.print(" Amps RMS  ---  ");
  Watt = (AmpsRMS*240/1.2);
  // note: 1.2 is my own empirically established calibration factor
  // as the voltage measured at D34 depends on the length of the OUT-to-D34 wire
  // 240 is
  Serial.print(Watt);
  Serial.println(" Watts");
  delay (100);

  display.clearDisplay();  // Clear the display
  display.setTextSize(1);
  display.setCursor(20, 2);
  display.print(" PIEZO GENERATOR ");
  display.setTextSize(1);
  display.setCursor(0,16);
  display.print(" VOLTAGE : ");
  display.setCursor(80, 16);
  display.print(voltage, 4); //decimals
  display.setTextSize(1);
  display.setCursor(0, 34);
  display.print(" CURRENT : ");
  display.setCursor(80, 34);
  display.print(AmpsRMS, 4); //decimals
  display.setTextSize(1);
  display.setCursor(0, 52);
  display.print(" POWER : ");
  display.setCursor(80, 52);
  display.print(voltagePiezo, 4); //decimals
  display.display(); // Update the display

  Serial.print("Input Voltage = ");
  Serial.println(voltage, 4); //decimals
  Serial.print("Current = ");
  Serial.println(AmpsRMS, 4); //decimals
  Serial.print("Power = ");
  Serial.println(Watt, 4); //decimals
  Serial.println();

  // Send data to Blynk
  Blynk.virtualWrite(V1, voltage);
  Blynk.virtualWrite(V2, AmpsRMS);
  Blynk.virtualWrite(V3, voltagePiezo);
}

[Madhukesh]

please edit your post, using the pencil icon at the bottom, and add triple backticks at the beginning and end of your code so that it displays correctly. Triple backticks look like this: ```

[PeteKnight]

@marksds Please edit your post, using the pencil icon at the bottom, and add triple backticks at the beginning and end of your code so that it displays correctly.
Triple backticks look like this:
```

Copy and paste these if you can’t find the correct symbol on your keyboard.

Pete.

[marksds]

already edited but do u know any solution to this?

[PeteKnight]

@marksds

int sensorIn = 27;

@marksds

readValue = analogRead(sensorIn);

You can’t use GPIO27 as an analog input when you’re using WiFi, because GPIO27 is connected to ADC2, and the ESP32 doesn’t support ADC2 and WiFi at the same time.

You should read this, and choose an ADC1 pin instead…

Connecting Blynk and ESP32

The reason that your sensors work without Blynk, but won’t work with Blynk is that you’ve chosen analog pins that are connected to the ESP33’s ADC2 analog to digital converter. The ESP32 architecture doesn’t allow ADC2 to be used at the same time as WiFi. You should choose pins that are connected to ADC1 instead… ADC1_CH0 (GPIO 36) ADC1_CH1 (GPIO 37) ADC1_CH2 (GPIO 38) ADC1_CH3 (GPIO 39) ADC1_CH4 (GPIO 32) ADC1_CH5 (GPIO 33) ADC1_CH6 (GPIO 34) ADC1_CH7 (GPIO 35) Read this for more info… B…

There are quite a few other issues with your code though, which will lead to problems with Blynk in future.

Pete.

[marksds]

i tried to follow your method but it still not working

[PeteKnight]

More info required.

Pete.

[marksds]

still not displaying the text everytime i include the

Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);

[PeteKnight]

So, I went into detail to point-out why the GPIO pin you’re using won’t work for analog input when using Blynk, and your responses are…

@marksds

i tried to follow your method but it still not working

and quoting an unrelated line of code from your original sketch.

If you don’t want to provide information about the changes you’ve made to your sketch, the results you’re now seeing, whether your device is online, what you’re seeing in your serial monitor, what the role of the Arduino is in your hardware setup, etc, etc, then that’s fine by me - just don’t expect a solution unless you provide more info.

Pete.

[marksds]

I just changed the pins like what you told to me. but the oled screen is not showing anything unless I remove the " Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass); "

#define BLYNK_TEMPLATE_NAME "Voltage sensor"
#define BLYNK_TEMPLATE_ID "TMPL6VbgjbzCM"
#define BLYNK_AUTH_TOKEN "ifBiQP3zJjkBqhgTR7QyLpauvG3w-NAG"

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

// setup OLED display
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET 4
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

//current
int sensorIn = 32;      // pin where the OUT pin from sensor is connected on Arduino
int mVperAmp = 185;           // this the 5A version of the ACS712 -use 100 for 20A Module and 66 for 30A Module
int Watt = 0;
double Voltage = 0;
double VRMS = 0;
double AmpsRMS = 0;

//voltage
int voltage_offset = 33;

//piezo
int sensorOutput = 34; //piezo
int ledPin = 35; // pin connected to LED
int threshold = 100;

BlynkTimer timer;

char ssid[] = "Hulaanmo"; // Your WiFi SSID
char pass[] = "Hulaanmo"; // Your WiFi password

float getVPP()
{
  float result;
  int readValue;                // value read from the sensor
  int maxValue = 0;             // store max value here
  int minValue = 4096;          // store min value here ESP32 ADC resolution
  
  uint32_t start_time = millis();
  while((millis()-start_time) < 1000) //sample for 1 Sec
  {
      readValue = analogRead(sensorIn);
      // see if you have a new maxValue
      if (readValue > maxValue) 
      {
          /*record the maximum sensor value*/
          maxValue = readValue;
      }
      if (readValue < minValue) 
      {
          /*record the minimum sensor value*/
          minValue = readValue;
      }
  }
   
  // Subtract min from max
  result = ((maxValue - minValue) * 3.3)/4096.0; //ESP32 ADC resolution 4096
      
  return result;
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

  pinMode(ledPin, OUTPUT); // declare led connected pin as output
  pinMode(sensorOutput, INPUT_PULLDOWN); // enable internal pull-down resistor

  // Initialize OLED display
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.clearDisplay();
  display.display();

  // Connect to WiFi
  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
  Serial.println("Initializing Blynk...");

  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);

  // Setup Blynk timer
  timer.setInterval(1000L, sendSensorData);
}

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

void sendSensorData() {
  int volt = analogRead(14);// read the input - GPIO_NUM_34
  double voltage = map(volt,0, 4096, 0, 1650) + voltage_offset;

  voltage /= 100; // divide by 100 to get the decimal values
  Serial.print("Voltage: ");
  Serial.print(voltage);
  Serial.println("V");

  delay(500);

  int sensorValue = 0; // default value when no sensor is connected
  sensorValue = analogRead(sensorOutput); // read analog voltage from sensor
  delay(10); // debounce the sensor input

  // Calculate the voltage based on the analog reading
  float voltagePiezo = sensorValue * (5.0 / 1023.0);

  Serial.print(" | Voltage: ");
  Serial.print(voltagePiezo);
  Serial.println(" V");

  if (sensorValue >= threshold) { // check voltage level from sensor
    digitalWrite(ledPin, HIGH);
    Serial.println("LED is ON");
  } else {
    digitalWrite(ledPin, LOW);
    Serial.println("LED is OFF");
  }
  delay(500); // wait 500ms before taking the next reading

  Voltage = getVPP();
  VRMS = (Voltage/2.0) *0.707;   //root
    AmpsRMS = ((VRMS * 1000)/mVperAmp)-0.13;
  Serial.print(AmpsRMS);
  Serial.print(" Amps RMS  ---  ");
  Watt = (AmpsRMS*240/1.2);
  // note: 1.2 is my own empirically established calibration factor
  // as the voltage measured at D34 depends on the length of the OUT-to-D34 wire
  // 240 is
  Serial.print(Watt);
  Serial.println(" Watts");
  delay (100);

  display.clearDisplay();  // Clear the display
  display.setTextSize(1);
  display.setCursor(20, 2);
  display.print(" PIEZO GENERATOR ");
  display.setTextSize(1);
  display.setCursor(0,16);
  display.print(" VOLTAGE : ");
  display.setCursor(80, 16);
  display.print(voltage, 4); //decimals
  display.setTextSize(1);
  display.setCursor(0, 34);
  display.print(" CURRENT : ");
  display.setCursor(80, 34);
  display.print(AmpsRMS, 4); //decimals
  display.setTextSize(1);
  display.setCursor(0, 52);
  display.print(" POWER : ");
  display.setCursor(80, 52);
  display.print(voltagePiezo, 4); //decimals
  display.display(); // Update the display

  Serial.print("Input Voltage = ");
  Serial.println(voltage, 4); //decimals
  Serial.print("Current = ");
  Serial.println(AmpsRMS, 4); //decimals
  Serial.print("Power = ");
  Serial.println(Watt, 4); //decimals
  Serial.println();

  // Send data to Blynk
  Blynk.virtualWrite(V1, voltage);
  Blynk.virtualWrite(V2, AmpsRMS);
  Blynk.virtualWrite(V3, voltagePiezo);
}

[PeteKnight]

@marksds

int volt = analogRead(14);// read the input - GPIO_NUM_34

Pete.

[marksds]

oled screen still not displaying, but if i remove the " Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass); " oled is displaying.

oled pins are
SDA is at GPIO21
SCL is at GPIO 22
GND is at GND pin
VCC is at 3.3V

#define BLYNK_TEMPLATE_NAME "Voltage sensor"
#define BLYNK_TEMPLATE_ID "TMPL6VbgjbzCM"
#define BLYNK_AUTH_TOKEN "ifBiQP3zJjkBqhgTR7QyLpauvG3w-NAG"

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

// setup OLED display
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET 4
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

//current
int sensorIn = 32;      // pin where the OUT pin from sensor is connected on Arduino
int mVperAmp = 185;           // this the 5A version of the ACS712 -use 100 for 20A Module and 66 for 30A Module
int Watt = 0;
double Voltage = 0;
double VRMS = 0;
double AmpsRMS = 0;

//voltage
int voltage_offset = 33;

//piezo
int sensorOutput = 34; //piezo
int ledPin = 35; // pin connected to LED
int threshold = 100;

BlynkTimer timer;

char ssid[] = "Hulaanmo"; // Your WiFi SSID
char pass[] = "Hulaanmo"; // Your WiFi password

float getVPP()
{
  float result;
  int readValue;                // value read from the sensor
  int maxValue = 0;             // store max value here
  int minValue = 4096;          // store min value here ESP32 ADC resolution
  
  uint32_t start_time = millis();
  while((millis()-start_time) < 1000) //sample for 1 Sec
  {
      readValue = analogRead(sensorIn);
      // see if you have a new maxValue
      if (readValue > maxValue) 
      {
          /*record the maximum sensor value*/
          maxValue = readValue;
      }
      if (readValue < minValue) 
      {
          /*record the minimum sensor value*/
          minValue = readValue;
      }
  }
   
  // Subtract min from max
  result = ((maxValue - minValue) * 3.3)/4096.0; //ESP32 ADC resolution 4096
      
  return result;
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

  pinMode(ledPin, OUTPUT); // declare led connected pin as output
  pinMode(sensorOutput, INPUT_PULLDOWN); // enable internal pull-down resistor

  // Initialize OLED display
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.clearDisplay();
  display.display();

  // Connect to WiFi
  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
  Serial.println("Initializing Blynk...");

  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);

  // Setup Blynk timer
  timer.setInterval(1000L, sendSensorData);
}

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

void sendSensorData() {
  int volt = analogRead(36);// read the input - GPIO_NUM_34
  double voltage = map(volt,0, 4096, 0, 1650) + voltage_offset;

  voltage /= 100; // divide by 100 to get the decimal values
  Serial.print("Voltage: ");
  Serial.print(voltage);
  Serial.println("V");

  delay(500);

  int sensorValue = 0; // default value when no sensor is connected
  sensorValue = analogRead(sensorOutput); // read analog voltage from sensor
  delay(10); // debounce the sensor input

  // Calculate the voltage based on the analog reading
  float voltagePiezo = sensorValue * (5.0 / 1023.0);

  Serial.print(" | Voltage: ");
  Serial.print(voltagePiezo);
  Serial.println(" V");

  if (sensorValue >= threshold) { // check voltage level from sensor
    digitalWrite(ledPin, HIGH);
    Serial.println("LED is ON");
  } else {
    digitalWrite(ledPin, LOW);
    Serial.println("LED is OFF");
  }
  delay(500); // wait 500ms before taking the next reading

  Voltage = getVPP();
  VRMS = (Voltage/2.0) *0.707;   //root
    AmpsRMS = ((VRMS * 1000)/mVperAmp)-0.13;
  Serial.print(AmpsRMS);
  Serial.print(" Amps RMS  ---  ");
  Watt = (AmpsRMS*240/1.2);
  // note: 1.2 is my own empirically established calibration factor
  // as the voltage measured at D34 depends on the length of the OUT-to-D34 wire
  // 240 is
  Serial.print(Watt);
  Serial.println(" Watts");
  delay (100);

  display.clearDisplay();  // Clear the display
  display.setTextSize(1);
  display.setCursor(20, 2);
  display.print(" PIEZO GENERATOR ");
  display.setTextSize(1);
  display.setCursor(0,16);
  display.print(" VOLTAGE : ");
  display.setCursor(80, 16);
  display.print(voltage, 4); //decimals
  display.setTextSize(1);
  display.setCursor(0, 34);
  display.print(" CURRENT : ");
  display.setCursor(80, 34);
  display.print(AmpsRMS, 4); //decimals
  display.setTextSize(1);
  display.setCursor(0, 52);
  display.print(" POWER : ");
  display.setCursor(80, 52);
  display.print(voltagePiezo, 4); //decimals
  display.display(); // Update the display

  Serial.print("Input Voltage = ");
  Serial.println(voltage, 4); //decimals
  Serial.print("Current = ");
  Serial.println(AmpsRMS, 4); //decimals
  Serial.print("Power = ");
  Serial.println(Watt, 4); //decimals
  Serial.println();

[PeteKnight]

@PeteKnight

If you don’t want to provide information about the changes you’ve made to your sketch, the results you’re now seeing, whether your device is online, what you’re seeing in your serial monitor, what the role of the Arduino is in your hardware setup, etc, etc, then that’s fine by me - just don’t expect a solution unless you provide more info.

Pete.

[marksds]

I already provide the change code?

u told me to change the GPIO 14 to GPIO PINS UNDER ADC_1 and I already provide it up there

[marksds]

it shows that it is connected to wifi. that’s what i see on my serial monitor, my main problem is the oled is not displaying everytime I add the blynk code

[PeteKnight]

Okay, I can’t help in that case.

Pete.

[marksds]

how sad, but why others can do blynk on esp

[PeteKnight]

Other people are prepared to provide information, so its possible to help them with their issues. You aren’t, so I can’t help.

Pete.

[marksds]

I already provided the information you need but still cant?

[marksds]

u told me sir to change the line and after I changed it I provide the code even the pins for what Im using on my oled screen. how come sir?