Arduino Uno and HC-08 BLE Bluetooth module - no connection


I have an Arduino Uno together with the suitable Adafruit motor shield for a RC car. So I needed a wireless connection for the Uno and decided to buy a HC-08 Bluetooth module.
I never had problems with my Blynk projects but in this case nothing seems to work. Even the Arduino_101_BLE example script can not be loaded onto the Uno and gives a compiling error. Btw I use the pins 10 and 11 for RX and TX because I read that it can lead to problems if the pins 0 and 1 are used.

The BLE module is working fine and I get an immediate connection with the LightBlue App on my iPhone. I created a simple Blynk project where I put a button and the Bluetooth widget onto my screen. But the Bluetooth widget is not working and is not able to find the device.
I followed this tutorial:

I’m not so experienced that I understand all the Bluetooth BLE stuff and deep programming issues. It would be great if someone could provide me with an code example or an explanation which is easy to understand.

Thanks a lot!

Posting the exact code you are using (correctly formatted with triple backticks of course) and specific details of the exact wiring would be a good starting point.


Hi Pete,

sorry, here is my latest try after I read a lot on Github about using SwSerial and SerialBLE …
But the code here is also not working because I get the message that SerialBLE is not defined in this scope. I don’t know if I used the triple backticks in the right way …

#define BLYNK_PRINT Serial

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

#include <BlynkSimpleSerialBLE.h>

// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "123456"; // my token

void setup()
  // Debug console

  Blynk.begin(SerialBLE, auth);

  Serial.println("Waiting for connections...");

void loop()

@Vetinari please edit your post, using the pencil icon at the bottom, and add triple backticks at the beginning and end of the code so that it displays correctly.
Triple backticks look like this:


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