How do I get iBeacon to Raspbberry PI working on iPhone? - bluetooth

Question

I have a Raspberry PI with a Cambridge Scientific USB adapter on which I've un the following:
sudo hciconfig hci0 up
sudo hciconfig hci0 leadv 3
sudo hcitool -i hci0 cmd 0x08 0x0008 1E 02 01 06 1A FF 4C 00 02 15 C7 C1 A1 BF BB 00 4C AD 87 04 9F 2D 29 17 DE D2 00 00 00 00 C8 00
I have written a MacOS Cocoa App as follows:
import Cocoa
import CoreBluetooth
class ViewController: NSViewController {
override func viewDidLoad() {
super.viewDidLoad()
BeaconScanner(type: BeaconType.iBeacon).scanEverySecond()
}
}
enum BeaconType {
case iBeacon
}
struct Beacon {
var uuid: NSUUID!
var major: UInt16!
var minor: UInt16!
var power: Int8!
var peripheral: CBPeripheral!
var advertisementData: NSDictionary!
var RSSI: NSNumber!
init(peripheral: CBPeripheral, advertisementData: NSDictionary, RSSI: NSNumber) {
self.peripheral = peripheral
self.advertisementData = advertisementData
self.RSSI = RSSI
}
private func getBytes(data: Any?, from: Int, count: Int) -> [CUnsignedChar] {
var bytes = [CUnsignedChar](repeating: 0, count: count)
(data! as AnyObject).getBytes(&bytes, range: NSMakeRange(from, count))
return bytes
}
private func getBytesAsUshort(data: Any?, from: Int) -> ushort {
var bytes = ushort()
(data! as AnyObject).getBytes(&bytes, range: NSMakeRange(from, 2))
return NSSwapShort(bytes)
}
private func getBytesAsInt8(data: Any?, from: Int) -> Int8 {
var bytes = Int8()
(data! as AnyObject).getBytes(&bytes, range: NSMakeRange(from, 1))
return bytes
}
func checkAdvertisementDataForPossibleiBeaconData() {
let beaconStandard: [CUnsignedChar] = [0x4c, 0x00, 0x02, 0x15]
var data = advertisementData.value(forKey: "kCBAdvDataManufacturerData")
if(data != nil) {
data = data as! Data
var beaconStandardBytes = [CUnsignedChar](repeating: 0, count: 4)
(data! as AnyObject).getBytes(&beaconStandardBytes, range: NSMakeRange(0,4))
if((data! as AnyObject).length >= 25 && beaconStandardBytes.elementsEqual(beaconStandard)) {
let uuid = NSUUID.init(uuidBytes: getBytes(data: data, from: 4, count: 16)) as UUID
let major = getBytesAsUshort(data: data, from: 20)
let minor = getBytesAsUshort(data: data, from: 22)
let power = getBytesAsInt8(data: data, from: 24)
let distance = calculateBeaconDistance(Int(power), RSSI: Int(truncating: RSSI))
print("BeaconStandard=\(beaconStandard), UUID=\(uuid.uuidString), major=\(major), minor=\(minor), power=\(power), RSSI=\(String(describing: RSSI)), Distance=\(String(format: "%.2f", distance))m")
}
}
}
func calculateBeaconDistance(_ power: Int, RSSI: Int) -> Double {
let ratio = Double(RSSI) * 1.0 / Double(power)
return ratio < 1.0 ? pow(ratio, 10.0) : round(10*((0.89976) * pow(ratio, 7.7095) + 0.111)) / 10
}
}
class BeaconScanner: NSObject, CBCentralManagerDelegate {
var cbManager: CBCentralManager!
var timer: Timer!
var type: BeaconType!
init(type: BeaconType) {
self.type = type
}
func scanEverySecond() {
cbManager = CBCentralManager(delegate: self, queue: nil)
self.timer = Timer.scheduledTimer(timeInterval: TimeInterval(1), target: self, selector: #selector(scan), userInfo: nil, repeats: true)
}
#objc func scan() {
if(cbManager != nil && cbManager.state.rawValue==CBManagerState.poweredOn.rawValue) {
cbManager.scanForPeripherals(withServices: nil, options: nil)
}
}
func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {
Beacon(peripheral: peripheral, advertisementData: advertisementData as NSDictionary, RSSI: RSSI).checkAdvertisementDataForPossibleiBeaconData()
}
func centralManagerDidUpdateState(_ central: CBCentralManager) {
if(!(central.state.rawValue == CBManagerState.poweredOn.rawValue)) {
print("In order to user this tool, Bluetooth must be switched on\n")
exit(EXIT_FAILURE)
}
}
}
This seems to work just fine. I get the following:
BeaconStandard=[76, 0, 2, 21], UUID=C7C1A1BF-BB00-4CAD-8704-9F2D2917DED2, major=0, minor=0, power=-56, RSSI=Optional(-74), Distance=7.80m
BeaconStandard=[76, 0, 2, 21], UUID=C7C1A1BF-BB00-4CAD-8704-9F2D2917DED2, major=0, minor=0, power=-56, RSSI=Optional(-76), Distance=9.60m
I then built an iOS app simply copying the ViewController code replacing
import Cocoa
import CoreBluetooth
class ViewController: NSViewController {
override func viewDidLoad() {
super.viewDidLoad()
BeaconScanner(type: BeaconType.iBeacon).scanEverySecond()
}
}
with
import UIKit
import CoreBluetooth
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
BeaconScanner(type: BeaconType.iBeacon).scanEverySecond()
}
}
I ran the code for about 5 minutes on iOS but got no hits.
I added some debug code and I do see hits from other Bluetooth devices, but none from the PI.
MacOS is running 10.14.6. iOS is running 12.3.1 and XCode is running 10.3.
Is this a hardware limitation? I know the CSR Bluetooth is pretty cheap. Or do I have a problem in the code?