Code Block
Code Block
I want to connect a bluetooth glucose meter device (Contour One) on macos 10.15 for development reasons.
Any read/write operation to the characteristics fails with this message:
020-12-12 12:18:36.461254+0100 bluetooth.test[1587:48116] [CoreBluetooth] WARNING: Unknown error: -536870212
The console app of macos shows the following:
standard 12:18:36.349729+0100 bluetoothd Read Device Name: c7532430
standard 12:18:36.393712+0100 bluetoothd *** [handleATTErrorResponse].
fehler 12:18:36.393780+0100 bluetoothd * [handleATTErrorResponse] - Insufficient Encryption.
standard 12:18:36.393820+0100 bluetoothd * [handleATTErrorResponse] - Link is not encrypted, perform pairing with MITM disbled.
standard 12:18:36.393858+0100 bluetoothd * [startLESecurityManagerPairingSecureConnection] Start secure pairing with mitm: 0, bonding: 1, sc: 1, keypress: 0, ct2: 0
standard 12:18:36.394505+0100 bluetoothd * [startLESecurityManagerPairingSecureConnection] - Master: _localAuthReq: 0x9, localInitiatorKeyDistribution: 0x3, localResponderKeyDistribution: 0x3
standard 12:18:36.394572+0100 bluetoothd * [pairingRequest] Send Pairing Request: auth 0x9
standard 12:18:36.417047+0100 bluetoothd * [l2capChannelData] - Received Pairing Failed.
fehler 12:18:36.417088+0100 bluetoothd *[handlePairingFailed] reason = 5.
fehler 12:18:36.418854+0100 bluetooth.test WARNING: Unknown error: -536870212
What happened here? Obviously I cannot pair the device by accepting the code provided by the device.
But CBCentral connect to the device as you can see here:
Bluetooth powered on.
Device Contour7802H6798544 found, try to connect...
Connected to Contour7802H6798544
***************************************************
Service: <CBService: 0x102805a70, isPrimary = NO, UUID = Glucose>
<CBCharacteristic: 0x102807700, UUID = 2A18, properties = 0x10, value = (null), notifying = NO>
... has notify
<CBCharacteristic: 0x1004300a0, UUID = 2A34, properties = 0x10, value = (null), notifying = NO>
... has notify
<CBCharacteristic: 0x1004302d0, UUID = 2A51, properties = 0x2, value = (null), notifying = NO>
... has read
<CBCharacteristic: 0x100430600, UUID = 2A52, properties = 0x28, value = (null), notifying = NO>
... has write
2020-12-12 19:49:52.921429+0100 bluetooth.test[620:10532] [CoreBluetooth] WARNING: Unknown error: -536870212
Optional(Error Domain=CBErrorDomain Code=0 "Unknown error." UserInfo={NSLocalizedDescription=Unknown error.})
2020-12-12 19:49:52.977537+0100 bluetooth.test[620:10659] [CoreBluetooth] WARNING: Unknown error: -536870212
*****************************************************
Error changing notification state:Optional("Unknown error.")
CBCharacteristicProperties(rawValue: 16)
I write to the 2A52 and it has write permission. But writing to the characteristic fails because macos denies due to missing encryption.
I have no idea for this case.
