Change the BLE MTU
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@Mark81 said in Change the BLE MTU:
Hi! Is there a way to change the default MTU for a Bluetooth Low Energy GATT server?
I have same question. My application is based on HeartRate example, and every time app starts, it tries to configure the MTU to 512, but is not possible and it goes to 23, as you can see bellow. I think the reason is the maximum MTU of my device is 247 (EFR32BG22 Silicon Labs). I don't find a way to change the default value of 512 that the HeartRate example imposes, so I need help.
D BluetoothGatt: connect() - device: 50:32:5F:CC:3D:3F, auto: false
D BluetoothGatt: registerApp()
D BluetoothGatt: registerApp() - UUID=77a9d5a3-9f10-42bb-8156-04653f2468ad
W QtBluetoothGatt: Using Android v26 BluetoothDevice.connectGatt()
D BluetoothGatt: onClientRegistered() - status=0 clientIf=9
D BluetoothGatt: onClientConnectionState() - status=0 clientIf=9 device=50:32:5F:CC:3D:3F
D BluetoothGatt: discoverServices() - device: 50:32:5F:CC:3D:3F
D BluetoothGatt: onConnectionUpdated() - Device=50:32:5F:CC:3D:3F interval=6 latency=0 timeout=500 status=0
D BluetoothGatt: onSearchComplete() = Device=50:32:5F:CC:3D:3F Status=0
D BluetoothGatt: configureMTU() - device: 50:32:5F:CC:3D:3F mtu: 512
W QtBluetoothGatt: MTU change initiated
D BluetoothGatt: readRssi() - device: 50:32:5F:CC:3D:3F
D QtBluetoothGatt: RSSI read initiated
D QtBluetoothGatt: RSSI read callback, rssi: -56, status: 0
W QtBluetoothGatt: Late RSSI read reply after timeout was hit
D BluetoothGatt: onConfigureMTU() - Device=50:32:5F:CC:3D:3F mtu=23 status=0
W QtBluetoothGatt: MTU changed to 23
W QtBluetoothGatt: Performing queued job, handle: 19 Read (false) ValueKnown: false Skipping: false Characteristic
D BluetoothGatt: onConnectionUpdated() - Device=50:32:5F:CC:3D:3F interval=36 latency=0 timeout=500 status=0
W QtBluetoothGatt: Performing queued job, handle: 20 Read (false) ValueKnown: false Skipping: true CharacteristicValue
W QtBluetoothGatt: Performing queued job, handle: 21 Read (false) ValueKnown: false Skipping: false Descriptor
W QtBluetoothGatt: Finished current discovery for service handle 18