Arduino Uno, HM-10 Bluetooth Module, Not Discoverable In short, I've hooked up an HM-10 to digital pins 10 and 11 on my Uno (required because TX/RX (0/1) can't be used whilst a serial connection is present). The Bluetooth module is a Sunfounder HM-10 which comes with a data sheet. I'm successfully communicating with the HM-10 and I've written a modified version of serial comms tutorial code provided so it stores the reads up in a buffer before outputting them which works fine, I can set all properties on the HM-10 using this method.

The delays were necessary as it seems the clock cycle can't 'keep up' - bytes go missing when reading/writing, so if I attempt to write by just using Serial.read() in loop() alone then not all of it is read/written.

Here's the code.

#include &lt;SoftwareSerial.h&gt;

SoftwareSerial mySerial(10, 11); // RX, TX

void setup()
{
  // Open serial communications and wait for port to open:
  Serial.begin(57600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }

  Serial.println("Goodnight moon!");

  delay(500);

  // set the data rate for the SoftwareSerial port
  mySerial.begin(9600);
  mySerial.print("Wake up wake up wake up wake up wake up! Wake up wake up wake up wake up wake up!");
}

void loop() // run over and over
{
  if (mySerial.available()) {
    String s = "";
    char c;
    while((c = mySerial.read()) != -1) {
      s += c;
      delay(10);
    }

    Serial.println("Received: " + s);
  }

  if (Serial.available()) {
    String s = "";
    char c;
    while((c = Serial.read()) != -1) {
      s += c;
      delay(10);
    }

    delay(10);

    Serial.println("Sent: " + s);

    mySerial.print(s);
  }
}


This allows me to show input and output as follows:

Sent: AT+ADDR?
Received: OK+ADDR:F4B85EB42D64
Sent: AT+ADVI?
Received: OK+Get:0
Sent: AT+ALLO?
Received: OK+Get:0
Sent: AT+BATT?
Received: OK+Get:077


So good so far. Here's what I can't figure out from the data sheet. How do I make the bluetooth module discoverable on, say, my Mac or from my iPhone? I've tested setting AT+ROLE0 or AT+ROLE1 followed by AT+RESET and also set AT+NAME so I know what to expect, yet I can't discover the module.

Also to note, the status LED is flashing as per the specification as an unconnected status (500ms high, 500ms low) which indicates AT+PIO10 is setup. AT+ADTY? is set to 0 which allows it to be advertising, responds to scanning and connectable.

I'm likely missing something quite obvious. Any ideas?
Ah, I jumped the gun. Just found out Mac/iPhone can't scan for BLE devices, so I downloaded a BLE scanning app and once I set AT+ROLE0 and AT+RESET it appeared.

So, the answer is you need a BLE scanning application.