How to change the characteristic property from "notify" to "indicate"?

[WrightLin]

Hi Sirs:

I am trying to change a characteristic property from "notify" to "indicate".

And the example I used was SDK15-> ble_app_uart.

I have ref these document：

• GATTS Handle Value Indication
• GATTC Handle Value Indication
• How to enable indication for a characteristic

And here is  what I've done so far:

fix tx_char's  property、hvx parameter。

 

-ble_nus.c/tx_char_add()

-ble_nus.c/ble_nus_data_send()

Catch indicate response - print log。

---

-main.c/ble_evt_handler()

fix  on_connect/on_write =>  check whether the property is notify or not.

---

-ble_nus.h

-ble_srv_common.c

-ble_nus.c/on_connect()

-ble_nus.c/on_write()

-ble_nus.c/ble_nus_data_send()

I test it with nrf_connect (android app), here is the result:

I could see that the property of tx_char is changed from "notify" to "indicate"

but when I sent data from the UART module, there was no response shown on the phone.

And  the RTT viewer didn't show any error log:

  

Is there any step I missed? Any suggestion will be great!!

Thank you!

[WrightLin]

here is my testing project. 
ble_app_uart_pm_justwork_bonding_indicate.rar

[Hung Bui]

Hi Lin, 

You would need to provide ble_nus.c and ble_nus.h so we can test here. 

Could you please check when you call ble_nus_data_send() do you get NRF_SUCCESS  ? 

A sniffer trace would be nice to have to see if the indication actually sent from the device or not. 

[WrightLin]

Hi Bui, thanks for your suggestion. 

I will try to record the packet by sniffer, and here is ble_nus.c/.h files.

ble_nus.rar

[WrightLin]

Hi Bui : 

I record the error code after ble_nus_data_send();

it return 8 , which means "NRF_ERROR_INVALID_STATE"

it's strange that when I ran the application in debug mode,  IDE didn't stop even it seems that there was some error just happened. 

[WrightLin]

Hi Bui: 

After I enable the indications property by nrfConnect "AGAIN", the application seems to work fine.
I have no idea why the application return error in the situation that I opened nrfConnect for the first time and the indication showed "enable".   Maybe it's a bug of nrfConnect? 

But this result means that the application code is working. Thanks for your help again!!