How to use Virtual pin of arduino through blynk to perform multiple task when button linked to virtual pin is pressed..?

Need Help With My Project
1

I’m trying to control robot path through UP, DOWN, LEFT and RIGHT through buttons in Blynk connected to virtual pins in Arduino. Is there any way I can push multiple commands under IF LOOP activating when virtual pin ==1 ?

2

Don’t forget to read the documentation :wink:

Try to stay away from blocking codes inside this function… but this is the normal way to use Virtual Pin control.

http://docs.blynk.cc/#blynk-main-operations-virtual-pins

BLYNK_WRITE(Vx) //Button Widget is writing to pin Vx
{
  if (param.asInt() == 1) { // activate next commands when button pressed ON
    // Do stuff here
    // and here
    // even here
  }
}
3

thx, but there is one more problem when i tried to upload the code it says the following error (same appears for BareMinimum code):
Arduino: 1.8.3 (Windows 10), Board: “Arduino/Genuino Uno”

Archiving built core (caching) in: C:\Users\ANISHG~1\AppData\Local\Temp\arduino_cache_129790\core\core_arduino_avr_uno_4f102434c573a4283b83ba95af927dff.a
Sketch uses 444 bytes (1%) of program storage space. Maximum is 32256 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
avrdude: ser_open(): can’t open device “\.\COM3”: The semaphore timeout period has expired.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
“Show verbose output during compilation”
option enabled in File -> Preferences.

I have uploaded several codes in arduino before and they worked but it’s the first time this has happened. I checked port from device manager and its COM3 my arduino is updated and i also tried restarting my pc and changing arduino usb cable but nothing works…:confused:

4

https://www.google.com/search?q=avrdude%3A+ser_open()%3A+can’t+open+device+“\.\COM3”%3A+The+semaphore+timeout+period+has+expired.&oq=avrdude%3A+ser_open()%3A+can’t+open+device+“\.\COM3”%3A+The+semaphore+timeout+period+has+expired.&aqs=chrome..69i57j69i58&sourceid=chrome&ie=UTF-8

5

Restarting windows worked for it.
For Virtual pin problem, it is still not working…
Here’s my code:

int ma1=2;
int mb1=3;
int ma2=7;
int mb2=8;
#define BLYNK_PRINT DebugSerial
#include <Servo.h>
int servoPin=5;
Servo myservo; 
int i=0;
#include <SoftwareSerial.h>

SoftwareSerial DebugSerial(0, 1); // RX, TX

#include <BlynkSimpleStream.h>

char auth[] = "57ac041e2a054fdb8d2368735c403f8a";

BLYNK_WRITE(V0)
        {
          myservo.write(param.asInt());
        }
BLYNK_WRITE(V1)
        {/*command for UP*/
          if(param.asInt()==1){
            digitalWrite(ma1,LOW);
            digitalWrite(mb1,HIGH);
            digitalWrite(ma2,LOW);
            digitalWrite(mb2,HIGH);
          }
          else{
            digitalWrite(ma1,LOW);
            digitalWrite(mb1,LOW);
            digitalWrite(ma2,LOW);
            digitalWrite(mb2,LOW);
          }
        }
BLYNK_WRITE(V2)
        {/*command for RIGHT*/
          if(param.asInt()==1){
            digitalWrite(ma1,LOW);
            digitalWrite(mb1,HIGH);
            digitalWrite(ma2,LOW);
            digitalWrite(mb2,LOW);
          }
          else{
            digitalWrite(ma1,LOW);
            digitalWrite(mb1,LOW);
            digitalWrite(ma2,LOW);
            digitalWrite(mb2,LOW);
          }
        }
BLYNK_WRITE(V3)
        {
          /*command for LEFT*/
          if(param.asInt()==1){
            digitalWrite(ma1,LOW);
            digitalWrite(mb1,LOW);
            digitalWrite(ma2,LOW);
            digitalWrite(mb2,HIGH);
          }
          else{
            digitalWrite(ma1,LOW);
            digitalWrite(mb1,LOW);
            digitalWrite(ma2,LOW);
            digitalWrite(mb2,LOW);
          }
        }
BLYNK_WRITE(V4)
        {
          /*command for DOWN*/
          if(param.asInt()==1){
            digitalWrite(ma1,HIGH);
            digitalWrite(mb1,LOW);
            digitalWrite(ma2,HIGH);
            digitalWrite(mb2,LOW);
          }
          else{
            digitalWrite(ma1,LOW);
            digitalWrite(mb1,LOW);
            digitalWrite(ma2,LOW);
            digitalWrite(mb2,LOW);
          }
        }
void setup()
{myservo.attach(servoPin);
  
  DebugSerial.begin(9600);
  Serial.begin(9600);
  Blynk.begin(Serial, auth);
}

void loop(){
  Blynk.run();
}
7

Should work… just perhaps not the way you want it to.

But it appears you haven’t set the pinmode() for any of those pins yet.

8

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