Virtual Pin can't read data

Need Help With My Project
1

Hi.
i am using Arduino Uno and 2 ultrasonic sensor and i use virtual pins to read data sensor. I have problems with virtual pins. I use 2 widget gauges. gauge1 for virtual pin 4 and gauge2 for virtual pin 8. Unfortunately only virtual 4 is reading data. Here is my source code.

#define TRIGGER  9
#define ECHO     10
#define TRIGGER1 7
#define ECHO1    6 

#define BLYNK_PRINT DebugSerial
#include <SoftwareSerial.h>
#include <SPI.h>
#include <Ethernet.h>
SoftwareSerial DebugSerial(10, 11); // RX, TX
    
#include <BlynkSimpleStream.h>


char auth[] = "my auth token";

BlynkTimer timer;

void notifyUptime()
{
  long uptime = millis() / 60000L;

  Blynk.notify(String("Running for ") + uptime + " minutes.");
}


BLYNK_WRITE(V1)
{
  int pinValue1 = param.asInt(); // assigning incoming value from pin V1 to a variable

}

BLYNK_WRITE(V2)
{
  int pinValue2 = param.asInt(); // assigning incoming value from pin V2 to a variable

}

BLYNK_WRITE(V3)
{
  int pinValue3 = param.asInt(); // assigning incoming value from pin V3 to a variable

}


BLYNK_WRITE(V4)
{
  int pinValue4 = param.asInt(); // assigning incoming value from pin V4 to a variable

}


BLYNK_WRITE(V5)
{
  int pinValue5 = param.asInt(); // assigning incoming value from pin V5 to a variable

}

BLYNK_WRITE(V6)
{
  int pinValue6 = param.asInt(); // assigning incoming value from pin V6 to a variable

}
BLYNK_WRITE(V7)
{
  int pinValue7 = param.asInt(); // assigning incoming value from pin V7 to a variable

}


BLYNK_WRITE(V8)
{
  int pinValue8 = param.asInt(); // assigning incoming value from pin V8 to a variable

}


void setup()
{
  DebugSerial.begin(9600);
  Serial.begin(9600);
  Blynk.begin(Serial, auth);
  pinMode(TRIGGER, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(TRIGGER1, OUTPUT);
  pinMode(ECHO1, INPUT);

   //Notify immediately on startup
   Blynk.notify("Device started");

  // Setup a function to be called every minute
  timer.setInterval(60000L, notifyUptime);
}

void loop()
{
  long duration, distance, duration1, distance1;
  digitalWrite(TRIGGER, LOW);  
  delayMicroseconds(2); 
  digitalWrite(TRIGGER1, LOW);  
  delayMicroseconds(2);
  
  digitalWrite(TRIGGER, HIGH);
  delayMicroseconds(10); 
  digitalWrite(TRIGGER1, HIGH);
  delayMicroseconds(10); 
  
  digitalWrite(TRIGGER, LOW);
  digitalWrite(TRIGGER1, LOW);
  duration = pulseIn(ECHO, HIGH);
  duration1 = pulseIn(ECHO1, HIGH);
  
  distance = (duration/2) / 29.1;
  Blynk.virtualWrite(V4, distance);
  distance1 = (duration1 /2) / 29.1;
  Blynk.virtualWrite(V8, distance1);

  //--------------first sensor-------------
  if(distance <= 1000)
  {
    Blynk.virtualWrite(V1, 255);
  }
  else
  {
    Blynk.virtualWrite(V1, 0);
  }
  if(distance <= 800)
  {
    Blynk.virtualWrite(V2, 255);
  }
  else
  {
    Blynk.virtualWrite(V2, 0);
  }
  if(distance <= 100)
  {
    Blynk.virtualWrite(V3, 255);
  }
  else
  {
    Blynk.virtualWrite(V3, 0);
  }
  
  if(distance <= 80)
  {
    Blynk.notify("Overflow! Please clean up the trash can");
  }
  
  //---------------second sensor-------------------
  if(distance1 <= 1000)
  {
    Blynk.virtualWrite(V5, 255);
  }
  else
  {
    Blynk.virtualWrite(V5, 0);
  }
  if(distance1 <= 800)
  {
    Blynk.virtualWrite(V6, 255);
  }
  else
  {
    Blynk.virtualWrite(V6, 0);
  }
  if(distance1 <= 100)
  {
    Blynk.virtualWrite(V7, 255);
  }
  else
  {
    Blynk.virtualWrite(V7, 0);
  }
  if(distance1 <= 4)
  {
    Blynk.email("my e-mail @gmail.com", "Subject: IoT Trash Can", "Overflow! Please clean up the trash can.");
  }
  
  delay(200);
  Blynk.run();
  timer.run();
}

i really need help.

2

@Natasha. You loop() is heavily loaded. Rewrite the program to have all reads triggerred by timers. Let loop() just contain blynk.run and timer.run. There should be no Blynk.virtualWrites in loop().

3
4

thank you and i do as u told but virtual pin 8 remain the same

#define BLYNK_PRINT DebugSerial
#define TRIGGER   9
#define ECHO      10
#define TRIGGER1  7
#define ECHO1     6

#include <SoftwareSerial.h>
SoftwareSerial DebugSerial(10, 11); // RX, TX
    
#include <BlynkSimpleStream.h>

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

// This function will be called every time Slider Widget
// in Blynk app writes values to the Virtual Pin V1
BLYNK_WRITE(V4)
{
  int pinValue4 = param.asInt(); // assigning incoming value from pin V1 to a variable

  // process received value
}

BLYNK_WRITE(V8)
{
  int pinValue8 = param.asInt(); // assigning incoming value from pin V1 to a variable

  // process received value
}


void setup()
{
  // Debug console
  DebugSerial.begin(9600);
  Serial.begin(9600);
  Blynk.begin(Serial, auth);
  pinMode(TRIGGER, OUTPUT);
  pinMode(TRIGGER1, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(ECHO1, INPUT);
  
}

void loop()
{
  long duration, distance, duration1, distance1;
  digitalWrite(TRIGGER, LOW);  
  delayMicroseconds(2); 
  digitalWrite(TRIGGER1, LOW);  
  delayMicroseconds(2);
  
  digitalWrite(TRIGGER, HIGH);
  delayMicroseconds(10); 
  digitalWrite(TRIGGER1, HIGH);
  delayMicroseconds(10);
  
  digitalWrite(TRIGGER, LOW);
  digitalWrite(TRIGGER1, LOW);
  
  duration = pulseIn(ECHO, HIGH);
  distance = (duration/2) / 29.1;
  Blynk.virtualWrite(V4, distance);
  
  duration1 = pulseIn(ECHO1, HIGH);
  distance1 = (duration1/2) / 29.1;
  Blynk.virtualWrite(V8, distance1);
  
  delay(200);
  Blynk.run();
}

did i miss something?

5

No you didn’t :stuck_out_tongue_winking_eye: As per the document I linked to above… With Blynk, you need to keep the void loop() more like this… and use Blynk Timer not delays.

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

Probably becasue your Blynk function is doing nothing but assigning the incoming value to a non-global variable that is never used inside the function and since it is not global, it can’t be used outside this function (not that it is anyhow).

https://www.arduino.cc/reference/en/language/variables/variable-scope--qualifiers/scope/

6

thank you very much for the info. i’ll try my hardest