BLYNK_WRITE(V5) // Executes when the value of virtual pin 5 changes
// execute this code if the switch widget is now ON
digitalWrite(2,HIGH); // Set digital pin 2 HIGH
digitalWrite(4,HIGH); // Set digital pin 4 HIGH
digitalWrite(5,HIGH); // Set digital pin 5 HIGH
digitalWrite(12,HIGH); // Set digital pin 12 HIGH
Blynk.virtualWrite(V1,1); // Turn the widget attached to V1 On
Blynk.virtualWrite(V2,1); // Turn the widget attached to V2 On
Blynk.virtualWrite(V3,1); // Turn the widget attached to V3 On
Blynk.virtualWrite(V4,1); // Turn the widget attached to V4 On
// execute this code if the switch widget is now OFF
digitalWrite(2,LOW); // Set digital pin 2 LOW
digitalWrite(4,LOW); // Set digital pin 4 LOW
digitalWrite(5,LOW); // Set digital pin 5 LOW
digitalWrite(12,LOW); // Set digital pin 12 LOW
Blynk.virtualWrite(V1,0); // Turn the widget attached to V1 Off
Blynk.virtualWrite(V2,0); // Turn the widget attached to V2 Off
Blynk.virtualWrite(V3,0); // Turn the widget attached to V3 Off
Blynk.virtualWrite(V4,0); // Turn the widget attached to V4 Off