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Virtual Pin to the Bluetooth (Unable to read ECG sensor)

Please help, I am not receiving any data on my and the Bluetooth keeps disconnecting every 5 seconds.
I am using Bluetooth Hm10 module and an ECG sensor as my input. Even though the device is online.

 #define BLYNK_USE_DIRECT_CONNECT

    // You could use a spare Hardware Serial on boards that have it (like Mega)
    #include <SoftwareSerial.h>
    SoftwareSerial DebugSerial(2, 3); // RX, TX

    #define BLYNK_PRINT DebugSerial
    #include <BlynkSimpleSerialBLE.h>

    // You should get Auth Token in the Blynk App.
    // Go to the Project Settings (nut icon).
    char auth[] = "7ba33741f39c4894a0b560104ed55498";

    BLYNK_READ(V5) // Widget in the app READs Virtal Pin V5 with the certain frequency
    {
      // This command writes Arduino's uptime in seconds to Virtual Pin V5
      Blynk.virtualWrite(5,  analogRead(A0));
    }

    void setup()
    {
      // Debug console
      DebugSerial.begin(9600);

      // Blynk will work through Serial
      // Do not read or write this serial manually in your sketch
      Serial.begin(9600);
      Blynk.begin(Serial, auth);
    }

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

You sketch doesn’t show how you are reading your sensor…

Also, is your device online or is it disconnecting, it is a bit hard to do both (although BT can sometimes seem that way :wink: )

If constant disconnection, that generally means either too much data or other interference.

You are awesome Gunner!
Im getting an error
after #simpletimer.h

Blynk_Release_v0.4.6\libraries\Blynk\examples\Boards_Bluetooth\Serial_HM10_HC08\Serial_HM10_HC08.ino:33:25: fatal error: SimpleTimer.h: No such file or directory

 #include <SimpleTimer.h>

You can remove that #include <SimpleTimer.h> line as BlynkTimer (same thing) is now built into the Blynk library (but you will need to upgrade to the 0.4.7 library first)

1 Like

Thanks I have updated it, here is the new code;
But theres is another error;

Serial_HM10_HC08:43: error: ‘sensorData’ was not declared in this scope

    #define BLYNK_USE_DIRECT_CONNECT

    // You could use a spare Hardware Serial on boards that have it (like Mega)
    #include <SoftwareSerial.h>
    SoftwareSerial DebugSerial(2, 3); // RX, TX

    #define BLYNK_PRINT DebugSerial
    #include <BlynkSimpleSerialBLE.h>


    SimpleTimer timer;

    // You should get Auth Token in the Blynk App.
    // Go to the Project Settings (nut icon).
    char auth[] = "7ba33741f39c4894a0b560104ed55498";

    BLYNK_READ(V5) //Blynk app has something on V5
    {
      sensorData = analogRead(A0); // reading the sensor on A0
      Blynk.virtualWrite(V5, sensorData); // sending to Blynk
    }

    void setup()
    {
      // Debug console
      DebugSerial.begin(9600);

      // Blynk will work through Serial
      // Do not read or write this serial manually in your sketch
      Serial.begin(9600);
      Blynk.begin(Serial, auth);
    }

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

Now you are getting into basic Arduino - need to know stuff :wink: https://www.arduino.cc/en/Guide/HomePage

Add this line below your #includes to declare sensorData as a global variable

int sensorData;

Also, be aware that if your sensor is spitting out data, you might run into BT disconnections. This is where you need to actually set up a timer, which you haven’t done quite yet.

But I think?? you might be OK if your display widget is set to a timed polling mode instead of PUSH. I honestly haven’t needed to use BLYNK_READ() at all, so this is a guess :wink:

I always do something like that this way:

timer.setInterval(1000L, readSensor); // Put this in void Setup()
void readSensor()  // sensor loop
{
  sensorData = analogRead(A0); // reading the sensor on A0
  Blynk.virtualWrite(V5, sensorData); // sending to Blynk
}

So far, ; the TX RX button are not in blinking, I am using “Bluetooth” as my device for connection on the Blynk App.
The Blynk App giving an error something is wrong with your bluetooth.

#define BLYNK_USE_DIRECT_CONNECT

// You could use a spare Hardware Serial on boards that have it (like Mega)
#include <SoftwareSerial.h>
SoftwareSerial DebugSerial(2, 3); // RX, TX

#define BLYNK_PRINT DebugSerial
#include <BlynkSimpleSerialBLE.h>

int sensorData;

SimpleTimer timer;


char auth[] = "7ba33741f39c4894a0b560104ed55498";

void readSensor()  // sensor loop
{
  sensorData = analogRead(A0); // reading the sensor on A0
  Blynk.virtualWrite(V5, sensorData); // sending to Blynk
}
void setup()
{

  timer.setInterval(1000L, readSensor); 
  DebugSerial.begin(9600);


  Serial.begin(9600);
  Blynk.begin(Serial, auth);
}

void loop()
{

  Blynk.run();
   timer.run();
}`Preformatted text`

Im also using a bluetooth debug app, the bluetooth keeps connecting and disconnecting.

Bluetooth and BLE are still in beta. You can try running a logging version of Blynk and help contribute to resolving the issues.

Thanks Gunner! I will try it.