I'm trying to listen to all Bluetooth connect/disconnect events. Even though the delegate's centralManagerDidUpdateState function is called, nothing happens when I connect or disconnect Bluetooth devices.
I'm confused as to what's going wrong. I initialize the Central Manager/delegate like this:
var btDelegate: CBCentralManagerDelegate = BluetoothDelegate()
var btManager = CBCentralManager(delegate: btDelegate, queue: nil)
BluetoothDelegate is defined like so:
import Foundation
import CoreBluetooth
class BluetoothDelegate : NSObject, CBCentralManagerDelegate {
func centralManager(central: CBCentralManager!, didConnectPeripheral peripheral: CBPeripheral!) {
println("connect") //this line is not called
}
func centralManager(central: CBCentralManager!, didDisconnectPeripheral peripheral: CBPeripheral!, error: NSError!) {
println("disconnect") //this line is not called
}
func centralManagerDidUpdateState(central: CBCentralManager!) {
println("state update") //this line is called
}
}
Note: I can continuously receive more state update events such as when I toggle Bluetooth, even though connect and disconnect are not called.
From your code it looks like you haven't started scanning for peripherals. Once you have confirmed that your central is in powered on state from centralManagerDidUpdateState method you should start scanning for your peripherals.
(The bluetooth devices you connected from bluetooth settings panel are irrelevant. You can't have access to them. (as far as I know) Incase you want to scan and find out your device on your own below code will help)
func centralManagerDidUpdateState(central: CBCentralManager!) {
switch (central.state) {
case CBCentralManagerState.PoweredOff:
break
case CBCentralManagerState.PoweredOn:
startScan() // start scanning once the bluetooth is On
break
default:
break
}
}
And your startScan method will be (You can provide service UUID, use nil if you want all )
func startScan(){
if let central = btManager {
central.scanForPeripheralsWithServices(nil, options: nil)
println("started Scanning")
}
}
After that whenever you discover a peripheral didDiscoverPeripheral method will be called first.
func centralManager(central: CBCentralManager!, didDiscoverPeripheral peripheral: CBPeripheral!, advertisementData: [NSObject : AnyObject]!, RSSI: NSNumber!) {
println(peripheral)
// btManager.connectPeripheral(peripheral, options: nil)
}
From there you collect the peripheral and then invoke connectPeripheral method of CBCentralManager. If the connection is successful didConnectPeripheral method will be called.
You should go through this documentation for complete details
Related
BLE works fine on 7 Plus (iOS 14.4.2) and 6 (iOS 12). But on XR (14.4.2) and 11 connection stuck after centralManager.connect(peripheral, options: nil) (infinite connection)
The peripheral is in connection mode because other smartphones cannot detect it.
At first I thought that the problem was with the radio module of the peripheral device itself (NRF52), but the problem also occurred with the debug board.
Rebooting the smartphone did not help.
It's funny that the app works fine on a MacBook with an M1 chip
Part of code:
// Peripheral model
init(withPeripheral peripheral: CBPeripheral, advertisementData advertisementDictionary: [String : Any], andRSSI currentRSSI: NSNumber, using manager: CBCentralManager) {
centralManager = manager
basePeripheral = peripheral
RSSI = currentRSSI
super.init()
advertisedName = parseAdvertisementData(advertisementDictionary)
basePeripheral.delegate = self
}
public func connect() {
centralManager.delegate = self
centralManager.connect(basePeripheral, options: nil)
print("Connecting to \(advertisedName ?? "device")...")
// logs stops here
}
public func disconnect() {
centralManager.cancelPeripheralConnection(basePeripheral)
print("Cancelling connection with \(advertisedName ?? "device")...")
// triggers on VC dismiss
}
func centralManagerDidUpdateState(_ central: CBCentralManager) {
if central.state != .poweredOn {
print("Central Manager stated changed to \(central.state)")
}
}
func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) {
if peripheral == basePeripheral {
print("Connected to \(advertisedName ?? "device")")
delegate?.peripheralDidConnect()
discoverPrimaryServices()
}
}
func centralManager(_ central: CBCentralManager, didDisconnectPeripheral peripheral: CBPeripheral, error: Error?) {
if peripheral == basePeripheral {
print("Disconnected from \(advertisedName ?? "device")")
delegate?.peripheralDidDisconnect()
}
}
"The peripheral is in connection mode because other smartphones cannot detect it." Did you mean that other smartphones can detect it?
Given the phones you've listed as working and not working, I would expect that your board is having trouble with Bluetooth 5 (which was first supported on the iPhone 8). The NRF52 supports BT5 (it supports 5.2), but if you've written your own firmware you may have broken the support. I'd start by making sure you're running the most vanilla code you can from Nordic.
I'm actually in informatics school and I have some trouble with the connection between my own self signed app coded in Swift(Xcode 11.3 and for IOS 13.2 device) and a BLE module SH-HC-08 plugged on an Arduino. (UUID : FE60E626-C58C-69F5-324F-43C7C409A93D)
I'm totally new into swift language and self-learning this way of thinking in this language.
I'm using CoreBluetooth to detect if the Bluetooth on my iPhone is On or off.
I can't actually check if my peripheral is detected, and can't send any information by my app.
(don't understand how to configure the methods in CoreBluetooth)
I downloaded apps caled LightBlue and BluetoothLE on app store. The first one give me fews information about my Bluetooth device and the second one allow me to sends Ascii Strings to my Arduino by my Bluetooth module.
LightBlue information 1:
LightBlue information 2:
BluetoothLE app:
As I said before, i already :
Import CoreBluetooth
Add CBCentralManagerDelegate & CBPeripheralDelegate to my class ViewController
instantiate CBCentralManager and CBPeripheral
setup the centralManagerDidUpdateState function
CoreBluetooth code:
import UIKit
import CoreBluetooth
var texteEnvoyer:String?
var test = false
class ViewController: UIViewController, CBCentralManagerDelegate, CBPeripheralDelegate {
var manager:CBCentralManager!
var module : CBPeripheral!
#IBOutlet weak var labelConnection: UILabel!
#IBOutlet weak var switchConnection: UISwitch!
#IBOutlet weak var labelTextField: UITextField!
#IBOutlet weak var labelTest: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
refresh()
manager = CBCentralManager(delegate: self, queue: nil)
}
func centralManagerDidUpdateState(_ central: CBCentralManager)
{
if(central.state == .poweredOff)
{
let alertController = UIAlertController(title: "Bluetooth", message: "Le bluetooth est déconnecté, veuillez l'activer et vous connecter au module.", preferredStyle: UIAlertController.Style.alert)
alertController.addAction(UIAlertAction(title: "OK", style: UIAlertAction.Style.default, handler: nil))
present(alertController, animated: true, completion: nil)
test = false
}
if(central.state == .poweredOn)
{
test = true
}
refresh()
}
I tried to play with the others methods like didDiscoverPeripheral or didConnected but I don't understand what i do and can't find any help to send information (preferred in String) by a self made application with bluetooth.
I tried that to discover my module but I don't have any "print" in my logs and don't know if my request was done or not... if I do it well or not too.
func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {
print("Name: \(peripheral.name)")
self.module = peripheral
self.module.delegate = self
if(peripheral.name == "SG-HC-08"){
manager.stopScan()
manager.connect(self.module, options: nil)
print(peripheral.name)
}
}
Someone have any experience with that or any help to give it will help me so much.
Thanks
Jikko,
I would be careful with using Global Variables.
Your global variables are the two declared outside of your class scope.
var texteEnvoyer:String?
var test = false
These can sometimes cause issues with your program such as memory leaks and retention. Im not saying that this is the case for you. But if you continue to develop and publish applications this may be something to rethink. Im sure for your purposes now this is totally fine.
To your point of "nothing in the console form the peripheral" we can try adding in some print statements to help us debug what is actually happening.
For starters:
func centralManagerDidUpdateState(_ central: CBCentralManager){
//.....
print("ENTERED THE FUNCTION")
if(peripheral.name == "SG-HC-08"){
manager.stopScan()
manager.connect(self.module, options: nil)
print("REACHED HERE")
}
}
IF in the console you see "REACHED HERE" then we know the code was called and executed. However this does not mean a successful connection.
If we do not see the print statement "ENTERED THE FUNCTION" , or "REACHED HERE" then that means there is a basic error. The function was never called or executed.
I would first create a function like so:
func startScan(){
if let central = manager {
central.scanForPeripheralsWithServices(nil, options: nil)
print("started Scanning")
}
}
And then in viewDidLoad()
call the start scan
override func viewDidLoad(){
super.viewDidLoad(animated)
startScan()
}
And then once you have discovered a peripheral use the didDiscoverPeripheral method (which will be called first)
func centralManager(_ central: CBCentralManager!, didDiscoverPeripheral peripheral: CBPeripheral!, advertisementData: [NSObject : AnyObject]!, RSSI: NSNumber!) {
print("DISCOVERED PERIPHERAL", peripheral)
// manager.connectPeripheral(peripheral, options: nil)
}
You can then connect to it once discovered.
Hope this helps
EDIT ----
try adding in these two lines to your function.
peripheral.delegate = self
peripheral.discoverServices(nil)
like so
func centralManager(_ central: CBCentralManager!, didDiscoverPeripheral peripheral: CBPeripheral!, advertisementData: [NSObject : AnyObject]!, RSSI: NSNumber!) {
print("DISCOVERED PERIPHERAL", peripheral)
// manager.connectPeripheral(peripheral, options: nil)
}
I forgot to add in the underscore "_" to the function parameters
func centralManager(_ central: ....) {}
--------------------^
Please find some informations on how delegation (1) and BLE (2) work.
1) When you instantiate your CBCentralObject manager, you pass your view controller (self) as the delegate of the central manager which means that some Bluetooth events handled by your central manager will be forwarded to your view controller.
In your case, it seems that you didn't implement the centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) method which is called every time a new peripheral is discovered.
Once you get the discovered peripheral, you can continue the process with the other delegates methods
2) If you want to communicate with a BLE device you have several steps to follow:
discover the device
connect to it
discover services and
characteristics
Then you can write data on any characteristic you want, or subscribe to listen to data emitted by your BLE device.
On iOS 10.1.1 discoverServices not working or error CoreBluetooth[ERROR] XPC connection interrupted, resetting occurs after call to discoverServices , or it gets immediatelly disconnected
I have iOS device that is central and other device Android based, that is peripheral. I scan for peripherals, then after user select device , call for connect peripheral and in didConnect call for discoverServices. But then problem happens. Tested same code on earlier iOS versions like (9.3 and 10.1 works without any problems 10/10 times). What could be a problem. On iOS 10.1.1 it succeeds every few times,but usually there is a problem
Here is code:
Everything is in separate mananger for Bluetooth communication
First I discover peripherals and put in in array:
func centralManager(_ central: CBCentralManager,didDiscover peripheral: CBPeripheral,advertisementData: [String : Any],rssi RSSI: NSNumber) {
peripherals.append(peripheral)
}
Via delegate I put names in tableView, and when user selects peripheral I take choosen peripheral from peripherals array and call:
func connect(_ peripheral:CBPeripheral) {
self.peripheralToConnect = peripheral
peripheral.delegate = self
if let manager = centralManager, manager.state == .poweredOn{
if (peripheral.state == .connected){
manager.cancelPeripheralConnection(peripheral)
}
if manager.isScanning {
manager.stopScan()
}
manager.connect(peripheral, options:nil)
}
}
func centralManager(_ central: CBCentralManager,didConnect peripheral: CBPeripheral) {
peripheral.delegate = self
peripheral.discoverServices(nil)
}
I have a question regarding CoreBluetooth programming in Mac OS X. I have some BLE beacons here that I want to detect. When I execute similar code on my iPhone, it seems to work just fine, but when I try this on my Mac, it seems to only notify of beacons in the neighbourhood every two seconds or so (or even more, but at least 2 seconds). The beacons are beaconing every 500ms, so I would expect to be notified every 500ms.
Is there someone out there who knows how I can tell Mac OS to be a little stricter with reporting the beacons?
I must say I'm quite new to Swift, so all comments on style will also be appreciated.
import Foundation
import CoreBluetooth
class CentralManagerDelegate : NSObject, CBCentralManagerDelegate {
func centralManagerDidUpdateState(central: CBCentralManager) {
if central.state == .PoweredOn {
central.scanForPeripheralsWithServices(nil, options: [CBCentralManagerScanOptionAllowDuplicatesKey : "YES"])
print("Started scanning")
}
else {
central.stopScan()
}
}
func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber) {
print("Beacon found with RSSI: " + RSSI.stringValue);
}
}
var _centralManagerDelegate = CentralManagerDelegate()
var _centralManager = CBCentralManager(delegate: _centralManagerDelegate, queue: dispatch_get_main_queue())
while true {
dispatch_main()
}
I am quite new to iOS programming and also to bluetooth protocol.
I have found a sample code written in swift and trying to modify it to work with my own bluetooth module. The module I have is DBM01 from dorji.
The service I need to use is FFF0 and the characteristics is FFF1 for sending a ASCII value.
When I use the LightBlue app on my macbook and connect to the board I have designed, which has the DBM01 module on it, I can send the char value of "1" and I get the expected response (Turning on a LED) and when I send value of "0" it turns the LED off.
Now with the code I have, I can connect to the DBM01 module. I can print its name. However, I cannot disconnect from it with the following function. I am also not sure if this is for disconnecting from the device or it is called automatically when the device is disconnected. Regardless, it does not work either way.
func centralManager(central: CBCentralManager,
didDisconnectPeripheral peripheral: CBPeripheral,
error: NSError?)
My main problem is I really didn't understand how I specify the service and the characteristics that I am interested in and connect to specific device that has them.
I am also unable to send a message. When I try I got the predefined error, since the following condition did't hold
if writeCharacteristic != nil
Below is my full code.
Appreciate if you can point out where I am doing wrong and how I can achieve connecting to specific device with specific service and characteristics information and sending data.
//
// ViewController.swift
// bleSwift
//
import UIKit
import CoreBluetooth
class ViewController: UIViewController, CBCentralManagerDelegate, CBPeripheralDelegate {
var centralManager: CBCentralManager!
var peripheral: CBPeripheral!
var writeCharacteristic: CBCharacteristic!
var service: CBService!
var characteristic: CBCharacteristic!
var bluetoothAvailable = false
let message = "1"
#IBOutlet weak var deviceName: UILabel!
#IBOutlet weak var ServiceName: UILabel!
#IBOutlet weak var CharacteristicsName: UILabel!
func centralManagerDidUpdateState(central: CBCentralManager)
{
print("Checking state")
switch (central.state)
{
case .PoweredOff:
print("CoreBluetooth BLE hardware is powered off")
case .PoweredOn:
print("CoreBluetooth BLE hardware is powered on and ready")
bluetoothAvailable = true;
case .Resetting:
print("CoreBluetooth BLE hardware is resetting")
case .Unauthorized:
print("CoreBluetooth BLE state is unauthorized")
case .Unknown:
print("CoreBluetooth BLE state is unknown");
case .Unsupported:
print("CoreBluetooth BLE hardware is unsupported on this platform");
}
if bluetoothAvailable == true
{
discoverDevices()
}
}
func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber)
{
// Stop scanning
self.centralManager.stopScan()
print("Stopped Scanning")
// Set as the peripheral to use and establish connection
//self.peripheral = peripheral
//self.peripheral.delegate = self
//self.centralManager.connectPeripheral(peripheral, options: nil)
peripheral.discoverServices([CBUUID(string: "FFF0")])
print("CONNECTED!!")
print(peripheral.name)
deviceName.text = peripheral.name
}
func discoverDevices() {
print("Discovering devices")
centralManager.scanForPeripheralsWithServices(nil, options: nil)
}
#IBAction func disconnectDevice(sender: AnyObject) {
func centralManager(central: CBCentralManager,
didDisconnectPeripheral peripheral: CBPeripheral,
error: NSError?)
{
print("CONNECTION WAS DISCONNECTED")
deviceName.text = "Disconnected"
}
}
#IBAction func Scan(sender: AnyObject)
{
print("Scan")
centralManager = CBCentralManager(delegate: self, queue: nil)
}
#IBAction func Send(sender: AnyObject)
{
let data = message.dataUsingEncoding(NSUTF8StringEncoding)
if writeCharacteristic != nil
{
print("Sent")
peripheral!.writeValue(data!, forCharacteristic: writeCharacteristic, type: CBCharacteristicWriteType.WithoutResponse)
}
else
{
print("Couldn't Send")
}
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
In order to send data to your ble peripheral, you should:
Start scanning.
In your ble central manager delegate you'll recieve didDiscoverPeripheral callback with discovered peripheral. Set yourself as its delegate and connect to it: centralManager.connectPeripheral(...)
Receive didConnectPeripheral in delegate. Now call discoverServices for this peripheral.
Recieve didDiscoverServices in your delegate. Finaly, call discoverCharacteristics for your service.
You'll recieve characteristic in didDiscoverCharacteristic delegate method. After that, you'll be able to send data to exact characteristic of your peripheral.
To disconnect peripheral, call method centralManager.cancelPeripheralConnection(...)