Use routines. When the IOS APP is connected, the notify function is not enabled, the Value is enabled

[myj]

Hi

  Use the following routine NRF\nRF5_SDK_17.1.0_ddde560\examples\ble_peripheral\ble_app_uart\pca10040\s132\arm5_no_packs.

  Use IOS APP Enable the data to be sent once. After the data is sent and received, the connection is disconnected. When the connection is reconnected, you can see the Value:

  The following video operations

You can only set the restart Bluetooth on the screen,Want to know why this is

[Hung Bui]

Hi Meary, 
Please correct me if I'm wrong, what you want to report is that:
1- Connect

2- Enable notification

3- See that the value is updated

4- Close the app

5- Connect again

6- Can't enable notification. Has to disable Bluetooth and enable Bluetooth again 

7- After that can enable notification ?


Have you tried to do disconnect before you close the app ? 

[myj]

Here's what I want：

1- Connect

2- Enable notification

3- See that the value is updated

4- Close the app

5- Connect again

6-Enable notification

7- See that the value is updated

but now in 5 Connect again later，the app none Enable notification，the value is  previous data retained.

[Hung Bui]

Hi Meary, 

myj said:

the app none Enable notification，the value is  previous data retained.

You meant you want the app to automatically enable notification ? Or you are saying that even if you press the enable notification button you still don't see the notification being enabled ? 
Note that for the device to automatically enable notification when connected you would need to bond the device with the phone and the device need to support storing the system attribute to be able to enable notification automatically  again. 

If you pressed the button but still don't see notification enabled, we would need to check on the nRF52 the command to write to CCCD attribute (enable notification ) is received. You may also want to use the sniffer trace to see what happens over the air. 

[myj]

As shown in the figure, the enable for the second point is not checked yet, while the Value value for the first point has already been marked.

[Hung Bui]

Hi Meary, 
Please clarify what you meant. 
I don't fully understand what you saying by "is not checked yet" . Did you press the button after you connect the 2nd time ?