Need to switch BLE off and on

RE: Need to switch BLE off and on

bjorn-spockeli — Fri, 01 Feb 2019 07:58:31 GMT

Understood. Let me know if you run in to any issues with the API mentioned below.

RE: Need to switch BLE off and on

Sergio T — Thu, 31 Jan 2019 18:00:35 GMT

Thanks Bjorn.

I'll try the BLE power on and off tomorrow and let you know here the result.

Usually I use a HW detector (my board will be supplied with AC voltage) so I detect mains failure within 20 ms. The advantage is I can stop the peripherals and controller while voltage is still OK, guaranteeing that the controller always starts when power gets back.I know that controllers have Brown Out Reset detectors but even those sometimes hang the controller when voltage oscillates around the detection point.

Anyway, I'll give it a try at a later stage.

Thanks for the tips.

RE: Need to switch BLE off and on

bjorn-spockeli — Thu, 31 Jan 2019 14:26:00 GMT

Hi Sergio,

Is the NRF51 powered by both battery and a power supply? If so how are you switching between battery and power supply?

The nRF51 has a Power Failure Comparator that can configured to generate an event when the supply voltage drops below a certain threshold, see the POFCON register in the nRF51 Reference Manual. You could also use the Low Power Comparator for this.

Q1: You can check the connection handle, m_conn_handle. It is non-zero if you have a connection and is set to BLE_CONN_HANDLE_INVALID = 0xFFFF if no connection is active. To disconnect you call sd_ble_gap_disconnect() with the connection handle and a hci_status_code.

Q2: Call sd_ble_gap_adv_stop() to stop advertising. The Radio will then be automatically switched off.

Q3: Call ble_advertising_start(BLE_ADV_MODE_FAST) to start advertising again.

Best regards
Bjørn