nRF51822 UART and BLE

RE: nRF51822 UART and BLE

Jørgen Holmefjord — Thu, 21 Apr 2022 10:09:40 GMT

Hi,

The correct approach would be to use the function sd_ble_gap_disconnect() and wait for the BLE_GAP_EVT_DISCONNECTED event. Note that the peripheral needs to start advertising when the Disconnected event is received, and the central needs to start scanning again when it wants to reconnect. It is not possible to initiate a connection from the central to the peripheral based on the address, if the peripheral is not advertising at the time.

Best regards,
Jørgen

RE: nRF51822 UART and BLE

Sahil Sawant — Tue, 19 Apr 2022 14:21:53 GMT

Thanks for your reply. So now I have written a code in the following sequence

1. Take a data from UART for 10 secs

2. Stop the UART and send start BLE ->send data over BLE for 10 secs

3. Stop BLE start UART again

I have used this approach and got a problem. BLE gets connected for only one time. In the second period, it does not show in the app. So could you tell me the API to terminate the BLE connection fully?

RE: nRF51822 UART and BLE

Jørgen Holmefjord — Tue, 19 Apr 2022 14:02:19 GMT

Hi,

The priorities of the softdevice are fixed, you are not able to change these, as the softdevice needs to handle strict timing requirements from the BLE specifications.

See "Exception (interrupt) management with a SoftDevice" on page 54-55 in S110 SoftDevice Specification v2.0 for more details.

If you need to receive data on UART while CPU is busy with BLE operations, you need to upgrade to a nRF52 series IC, which have UARTE peripherals with EasyDMA support, allowing you to send/receive data directly from/to RAM.

Best regards,
Jørgen