ESP32 Forum

Posted: **Tue Feb 07, 2023 9:10 pm**

Is it possible to have multiple concurrent BLE connections on the ESP32? The documentations says it supports up to 9 client devices, but I can't even get two concurrent connections using the GATT security server example code (https://github.com/espressif/esp-idf/tr ... ity_server). Is there something that I should be setting to get multiple connections? BLE 4.2 should support a higher number of connections regardless of its role (central vs peripheral).

Here's what I'm using as the client code (on two separate devices):

Code: [Select all] [Expand/Collapse]

import asyncio
from bleak import BleakScanner, BleakClient
 
address = 'f4:12:fa:d9:7f:52'
 
async def main(address):
    async with BleakClient(address, timeout=30) as client:
      for service in client.services:
        print('-------------------')
        print(service)
 
        for c in service.characteristics:
          print('+- ', c)
          if 'read' in  c.properties:
            print('   ', await client.read_gatt_char(c))
          else:
            print('   no read')
 
      await asyncio.sleep(100000)
 
 
asyncio.run(main(address))

Using the script above, I can get one client to connect and hold open its connection. But on the second device, it times out and I cannot connect to the BLE device.

ESP32 Forum

Multiple BLE connections

Multiple BLE connections