Introduction

Hot to read and write data to a bluetooth low energy device.

Remarks

Some important points

• No capabilities are needed.
• iPhone store bytes in Little Endian format, so check if bluetooth accessory use Little Endian too. Example:

- intel CPU usually use little endian.
- The ARM architecture was little-endian before version 3 when it became big-endian.

• After a single or batch operation the connection will be lost, so you have to reconnect before continue.

Scan for SERVICE UUID

func SearchBLE(){
    cb_manager.scanForPeripherals(withServices:[service_uuid], options: nil)
    StopSearchBLE()
}

How to discover SERVICE UUID without documentation

func centralManager(_ central: CBCentralManager, didConnect peripheral:             
CBPeripheral) {
        peripheral.delegate = self
        peripheral.discoverServices(nil)
}

func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {
    for service in peripheral.services! {
        print("Service: \\(service)\\n error: \\(error)")
    }
}

• discoverServices(nil) - NIL means that all services will be returned, which is not a good option.( READ Remarks 3)

• If you haven’t found the SERVICE UUID run your code and looking for in console

  

• I found have 3 services: Battery, Device information (Firmware) and FFF0

• This uuid service isn’t a standard one, a list with standards can find here

• FFF0 is the SERVICE UUID in this case