Button pressed, Arduino went offline

Solved
1

Hi guys,
i need to connect my Arduino that will check if button is pressed or not.
I needed also if Arduino was connected or not and I chose “notify when hardware goes offline” in notification settings.

Why Arduino goes offline when I press the button on pin 2?
I can use it only if I close serial monitor and run it again.

Another question: when I press button, in serial monitor I see a lot of “Button pressed”, but I press button only one time!!
Hope someone help me…
here code:

#define BLYNK_PRINT Serial

#include <SPI.h>
#include <Ethernet.h>
#include <BlynkSimpleEthernet.h>

// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = “xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx”;
// Mac address should be different for each device in your LAN
byte arduino_mac[] = { 0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xED };
IPAddress arduino_ip ( 192, 168, 1, 73);
IPAddress dns_ip ( 8, 8, 8, 8);
IPAddress gateway_ip ( 192, 168, 1, 254);
IPAddress subnet_mask(255, 255, 255, 0);
#define W5100_CS 10
#define SDCARD_CS 4

void notifyOnButtonPress()
{
// Invert state, since button is “Active LOW”
int isButtonPressed = !digitalRead(2);
if (isButtonPressed) {
Serial.println(“Button is pressed.”);

// Note:
//   We allow 1 notification per 15 seconds for now.
Blynk.notify("Yaaay... button is pressed!");

}
}

void setup()
{
pinMode(SDCARD_CS, OUTPUT);
digitalWrite(SDCARD_CS, HIGH); // Deselect the SD card
Serial.begin(9600);
Blynk.begin(auth, “blynk-cloud.com”, 8442, arduino_ip, dns_ip, gateway_ip, subnet_mask, arduino_mac);

// Setup notification button on pin 2
pinMode(2, INPUT_PULLUP);
// Attach pin 2 interrupt to our handler
attachInterrupt(digitalPinToInterrupt(2), notifyOnButtonPress, CHANGE);
}

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

2

It is because arduino is running @16mhz, so when you press down button, it will “flood” the server with blynk.notify, and your HW gets disconnected. Check out docs for more info about timers and how to use them.

3

Thanks @wiipro
I tried also this sketch with timer.
How can I do to implement notifing process on this?
Please help me.




 #define BLYNK_PRINT Serial    // Comment this out to disable prints and save space
#include <SPI.h>
#include <Ethernet.h>
#include <BlynkSimpleEthernet.h>
#include <SimpleTimer.h>

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

//IPAddress server_ip (blynk-cloud.com);

// Mac address should be different for each device in your LAN
byte arduino_mac[] = { 0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xED };
IPAddress arduino_ip ( 192,   168,   1,  73);
IPAddress dns_ip     (  8,   8,   8,   8);
IPAddress gateway_ip ( 192,   168,   1,   254);
IPAddress subnet_mask(255, 255, 255,   0);

#define W5100_CS  10
#define SDCARD_CS 4
// Select your pin with physical button
const int btnPin = 7;

WidgetLED led3(V3);

SimpleTimer timer;

void setup()
{
  Serial.begin(9600);
  Blynk.begin(auth, "blynk-cloud.com", 8442, arduino_ip, dns_ip, gateway_ip, subnet_mask, arduino_mac);
  // Or like this:
  //Blynk.begin(auth, "blynk-cloud.com", 8442, arduino_ip, dns_ip, gateway_ip, subnet_mask, arduino_mac);

  // Setup physical button pin (active low)
  pinMode(btnPin, INPUT_PULLUP);

  timer.setInterval(500L, buttonLedWidget);
}

// V3 LED Widget represents the physical button state
boolean btnState = false;
void buttonLedWidget()
{
  // Read button
  boolean isPressed = (digitalRead(btnPin) == LOW);

  // If state has changed...
  if (isPressed != btnState) {
    if (isPressed) {
      led3.on();
    } else {
      led3.off();
    }
    btnState = isPressed;
  }
}

void loop()
{
  Blynk.run();
  timer.run();
}
4

Try to add Blynk.notify(“blablabla”); to if (isPressed)

5

you also need to be aware of the limitations of Notify:

http://docs.blynk.cc/#widgets-notifications-push-notifications

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