iOS doesn't see changes to Bluetooth services and characteristics between sketches

[don]

iOS doesn't see changes to Bluetooth services and characteristics between sketches

To duplicate

1. Run example CurieBle -> LED
2. Use LightBlue from iPhone to connect to LED
3. Run example CurieBle -> ButtonLED
4. Use LightBlue from iPhone to connect to ButtonLED (the old LED name will be show)

Problem: The old LED characteristics are also shown

5. Turn Bluetooth off and on on the iPhone
6. Use LightBlue from iPhone to connect to ButtonLED

The correct service and characteristics should now be shown

Background

The original problem was that descriptors (0x2901) added to existing sketches were not showing up in LightBlue. This has not been a problem when using other libraries such as BLEPeripheral or bleno. The steps above are an easier way to duplicate the issue without adding descriptors.

Software/Hardware

Arduino 101
Arduino IDE 1.6.7 on OS 10.10.5
iOS 9.2 (13C75) on iPhone 6s

Possible solution

iOS is expecting Service Changed 0x2a05 to be implemented on the Generic Attribute Service 0x1801.

[mwms]

I had the same problem. Turn off and then turn on the bluetooth on iPhone.

[kitsunami]

@noelpaz , please work with Sidney on this.

[noelpaz]

This could be a Light Blue issue rather than a Arduino 101 issue. For some reason the Light Blue App cache's the Peripheral address and instead of reading the local name in the Advertising packet it just remembers the old values. This even get's worse if you bond. I would suggest getting the nRF Master Controller App instead of Light Blue. Or as mention kill the app or do a rescan

[sandeepmistry]

@kitsunami @noelpaz I've discussed this @calvinatintel.

I believe it's a caching issue with iOS in general, as @don mentioned if the Service Changed 0x2a05 characteristic is not present in the Generic Attribute Service 0x1801 iOS will cache all attributes even if the sketch changes them.

I suggest we do the following: add the 0x2a05 characteristic to the 0x1801 service by setting the services_changed property on the ble_gatts_enable_params_t parameter passed into sd_ble_enable needs to be set to true. (This might be a nRF51822 change).