Example
- I'm in a controlled room with a single minew beacon that use IBEACON protocol.
- BLEController needs to extend CBPeripheralDelegate
- I'll use the first BLE to connect after the search has stop.
- Modify the method StopSearchBLE()
class BLEController: CBCentralManagerDelegate, CBPeripheralDelegate{
//...
func StopSearchMiniewBeacon() {
let when = DispatchTime.now() + 5 // change 2 to desired number of seconds
DispatchQueue.main.asyncAfter(deadline: when) {
self.cb_manager.stopScan()
self.cb_manager.connect(bles.first)
}
}
/...
}
- In the documention of your BLE device, you should look for the SERVICE UUID and MAJOR UUID CHARACTERISTIC
var service_uuid = CBUUID(string: "0000fff0-0000-1000-8000-00805f9b34fb")
var major_uuid = CBUUID(string: "0000fff2-0000-1000-8000-00805f9b34fb")
func centralManager(_ central: CBCentralManager, didConnect peripheral:
CBPeripheral) {
peripheral.delegate = self
peripheral.discoverServices([service_uuid])
}
func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {
print("Service: \(service)\n error: \(error)")
peripheral.discoverCharacteristics([major_uuid], for: (peripheral.services?[0])!)
}
- Create a variable 'service_uuid' and 'major_uuid' like code above. '-0000-1000-8000-00805f9b34fb' is part of the standard. 'fff0' is my SERVICE UUID, 'fff2' is my MAJOR UUID characteristic and '0000' are required to fill the 4 bytes uuid 1ยบ block.
- discoverCharacteristics([major_uuid], for: (peripheral.services?[0])!) will get major characteristic from my device gatt server and it will have NIL as value for now.
- (peripheral.services?[0])! - 0 beacuse will return a single value once I did peripheral.discoverServices([service_uuid])
func peripheral(_ peripheral: CBPeripheral, didDiscoverCharacteristicsFor service: CBService, error: Error?) {
for characteristic in service.characteristics! {
print("Characteristic: \(characteristic)\n error: \(error)")
if(characteristic.uuid.uuidString == "FFF2"){
peripheral.readValue(for: characteristic)
}
}
}
func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) {
print("Characteristic read: \(characteristic)\n error: \(error)")
let major = UInt16.init(bigEndian: UInt16(data: characteristic.value!)!)
print("major: \(major)")
}
- Characteristic value will only be readable after call peripheral.readValue(for: characteristic)
- readValue will result in func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) with value in Data type.
