Sending Data with BLE

[cemalgnlts]

Hi,

I want to simply start BLE from my ESP-32 and connect with my phone, but my phone sees ble and gives this warning when I try to connect:
"Make sure the Bluetooth device is in pairing mode."

import bluetooth
from time import sleep

class BLE():
    def __init__(self, name):   
        self.name = name
        self.isConnected = False

        self.ble = bluetooth.BLE()
        self.ble.active(True)
        self.ble.irq(self.ble_irq)

        self.register()
        self.advertiser()


    # BLE interrupt request handler.
    def ble_irq(self, event, data):
        if event == 1:
            # _IRQ_CENTRAL_CONNECT: a central has connected
            self.isConnected = True
            print('Connected')
        elif event == 2:
            # _IRQ_CENTRAL_DISCONNECT: central has disconnected
            self.isConnected = False
            self.advertiser()
            print('Disconnected')
        elif event == 3:
            # _IRQ_GATTS_WRITE: client has written to RX characteristic
            buffer = self.ble.gatts_read(self.rx)
            message = buffer.decode('UTF-8').strip()
            print(message)            


    def register(self):        
        # Nordic UART Service (NUS)
        NUS_UUID = '6E400001-B5A3-F393-E0A9-E50E24DCCA9E'
        RX_UUID = '6E400002-B5A3-F393-E0A9-E50E24DCCA9E'
        TX_UUID = '6E400003-B5A3-F393-E0A9-E50E24DCCA9E'
            
        BLE_NUS = bluetooth.UUID(NUS_UUID)
        BLE_RX = (bluetooth.UUID(RX_UUID), bluetooth.FLAG_WRITE)
        BLE_TX = (bluetooth.UUID(TX_UUID), bluetooth.FLAG_READ | bluetooth.FLAG_NOTIFY)

        BLE_UART = (BLE_NUS, (BLE_TX, BLE_RX,))
        SERVICES = (BLE_UART, )
        ((self.tx, self.rx,), ) = self.ble.gatts_register_services(SERVICES)


    def send(self, data):
        self.ble.gatts_notify(0, self.tx, data + '\n')


    def advertiser(self):
        name = bytes(self.name, 'UTF-8')
        adv = b'\x02\x01\x06' + bytearray((len(name) + 1, 0x09)) + name
        self.ble.gap_advertise(100, adv)


ble = BLE("ESP32")
print("BT on")

while True:
    if ble.isConnected:
        ble.send("Hi")

    sleep(100)

[shariltumin]

You can try including these lines in your init:

    def __init__(self, name):
        self.name = name
        self.isConnected = False

        self.ble = bluetooth.BLE()

        #-----------------------------------
        # warning insecure - just work mode
        self.ble.config(bond=False)
        self.ble.config(le_secure=False)
        self.ble.config(mitm=False)
        self.ble.config(io=0) # IO_CAP_DISPLAY_ONLY
        #-----------------------------------

        self.ble.active(True)
        self.ble.irq(self.ble_irq)

        self.register()
        self.advertiser()

[cemalgnlts]

Thanks for the answer, but my device still wants me to use an app, so I tried the Serial Bluetooth Terminal app and it worked really well. However, when I worked with HC-05 before or used the BluetoothSerial library with cpp via Arduino IDE, I had no problems. I think it is called Bluetooth Classic, is there any way to access it with micropython?

I saw that you created a repo for this: https://github.com/shariltumin/esp32-bluetooth-classic-micropython
But what is the current situation?

[shariltumin]

Bluetooth Classic and Bluetooth Low Energy (BLE) are not the same thing. They are not compatible and cannot communicate with each other.

If you have a BLE peripheral (server), then you must also have a BLE central (client).

The ESP32 is the only MCU that supports Bluetooth Classic. All others support BLE only.

Standard MicroPython only supports BLE.

If you need Bluetooth Classic on an ESP32, you must build your own custom MicroPython firmware.

[cemalgnlts]

I understand better now, thanks.