UART service center

RE: UART service center

Hieu — Mon, 05 Jun 2023 19:41:09 GMT

This is tricky. The "example code" for this is already there in the same file, ble_nus_c.c. You simply have to replicate exactly what is done to the TX Characteristic.

Here are the functions you will want to refer to:

Enabling notification: ble_nus_c_tx_notif_enable()
This is a "public" function which is called from outside the module. You should see the RX Characteristic's CCCD being written.

Handle the data: ble_nus_c_on_ble_evt()
This is where the SoftDevice push raw BLE events to the application's modules, including ble_nus_c.c. You should look into how BLE_GATTC_EVT_HVX is handled from here to the point where ble_nus_c.c generate a BLE_NUS_C_EVT_NUS_TX_EVT and call the ble_nus_c_t's handler.

Asides from this, I think perhaps your difficulties lies with not fully understanding some concepts. Here are some things that I think most people will encounter for the first time around this stage. Please make sure they understand what they are.

- CCCD
- Attribute
- Attribute Handle
- The fact that Services, Characteristics, and Descriptors are just attributes

Let's start with this. Please look into what I listed above and let me know how it goes.

RE: UART service center

Taylor — Fri, 02 Jun 2023 01:13:51 GMT

In my opinion, on_hvx() returned the data and data length which have been enabled the charactertic notify. But the example just enabled the BLE_UUID_NUS_TX_CHARACTERISTIC's notify,so when the peripheral tansmit data from the BLE_UUID_NUS_RX_CHARACTERISTIC, we can not handle this.

In addition to this,the peripheral will disconnect automatically while tansmit data from BLE_UUID_NUS_RX_CHARACTERISTIC.

So I have no idea how wo enable the BLE_UUID_NUS_RX_CHARACTERISTIC's notify and handle the data.

RE: UART service center

Hieu — Thu, 01 Jun 2023 13:47:51 GMT

Could you please go into details what you are confused about on_hvx()? Or are you completely confused what it is and is looking for some starting points?

RE: UART service center

Taylor — Thu, 01 Jun 2023 09:42:20 GMT

Thanks for your reply.

I am so comfused of on_hvx(), could you tell me how to solve my problem?

RE: UART service center

Hieu — Tue, 30 May 2023 21:41:55 GMT

Hi Taylor,

Please look into how on_hvx() is implemented and used in ble_nus_c.c.

Hieu