iosbluetooth-lowenergycore-bluetoothbluetooth-gattios-bluetooth

Can we Change BLE MTU and characteristic sizes on iOS central and peripheral devices

I want MTU ATT size 247, But if In Our BLE hardware device sets MTU size 24 then the device is connected but if we change it to 247, then the iPhone device not going to connect with the BLE hardware device. So is any other way to connect with the BLE hardware device.

I am getting maximumWriteValueLength in my iPhone is 512

Solution

  • IOS always asks for an MTU of 185. So make sure your peripheral accepts that.

    If you want to check using maximumWriteValueLength(), make sure you pass the withoutResponse type. Otherwise you always get 512 which is the max characteristic length.