Microchip RN4020 -> MLDP mode iOS sample code - ios

Question

It has been now several years that Microchip has released the RN4020 BT LE chip with the private MLDP profile. However, as of yet there is STILL NO PUBLICLY AVAILABLE iOS sample source code available, despite them having an iOS App in the Apple App Store. Has anyone any working code and willing to share/post it?
Thanks!
Tim

Answer 1

I have some working code. I'll give some snippets here. In a first ViewController which conforms to the CBCentralManagerDelegate we have:
var cbc : CBCentralManager? = nil
override func viewDidLoad() {
super.viewDidLoad()
cbc = CBCentralManager(delegate: self, queue: nil)
}
touching a button starts scanning for peripherals
#IBAction func scan(_ sender: Any) {
cbc?.scanForPeripherals(withServices: nil, options: nil)
}
for each peripheral found the following delegate member will be called
func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {
// store peripherals here to let select user one
NSLog("name=%#", peripheral.name ?? "unnamed")
}
we store the peripherals in a dictionary and present its names to the user using a table view. If the user selects a peripheral we try to connect to that
#IBAction func connect(_ sender: Any) {
// selectedPeripheral set by selection from the table view
cbc?.connect(selectedPeripheral!, options: nil)
}
successfull connection will result in a call to the following delegate method:
func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) {
performSegue(withIdentifier: "ConnectPeriph", sender: self)
}
which leads to a second ViewController responsible for the connected state. This ViewController conforms to the CBPeripheralDelegate protocol and declares the following variables:
var periph : CBPeripheral! // selected peripheral
var dataChar : CBCharacteristic? // characteristic for data transfer
let mchpPrivateService : CBUUID = CBUUID(string: "00035B03-58E6-07DD-021A-08123A000300")
let mchpDataPrivateChar : CBUUID = CBUUID(string: "00035B03-58E6-07DD-021A-08123A000301")
first action after connection is to discover the services which the peripheral is offering:
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
periph.delegate = self
periph.discoverServices(nil)
}
this results in calls to this delegate method:
func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {
if let e = error {
NSLog("Error %#", e.localizedDescription)
}
else if let services = peripheral.services {
for s in services {
NSLog("Service=%#", s.uuid.uuidString)
if s.uuid.isEqual(mchpPrivateService) {
peripheral.discoverCharacteristics(nil, for: s)
}
}
}
}
which in turn results in discovering characteristics:
func peripheral(_ peripheral: CBPeripheral, didDiscoverCharacteristicsFor service: CBService, error: Error?) {
NSLog("characteristics for service %#", service.uuid.uuidString)
if let characteristics = service.characteristics {
for c in characteristics {
if c.uuid.isEqual(mchpDataPrivateChar) {
peripheral.setNotifyValue(true, for: c)
dataChar = c
}
}
}
}
the only characteristic we are interested in is that with the uuid mchpDataPrivateChar. The request for notification results in calls to:
func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) {
NSLog("update value for %#", characteristic.uuid)
if let d = characteristic.value {
var s : String = String()
for b in d {
s.append(Character(UnicodeScalar(b)))
}
NSLog("received \(d.count) bytes: \(s)")
}
}
which completes the receiver on the iOS side. Sending bytes is done via:
#IBAction func sendClicked(_ sender: Any) {
if let d = dataChar, let s=sendEdit.text {
let buffer : [UInt8] = Array(s.utf8)
let data : Data = Data(buffer)
periph.writeValue(data, for: d, type: .withResponse)
}
}