How often does rssisample register get updated

[nordicdev]

Hi,

If I need to get RSSI updates while the peripheral is in connected mode, I need to call sd_ble_gap_rssi_start() just after connection has established. Then the RSSI values would be automatically stored in RSSISAMPLE register. Then, I need to manually read this register whenever I need to know about RSSI. Are the above correct?

How often is the RSSI SAMPLE register updated?

[Joakim Jakobsen]

Hi Nordicdev.

Yes, you are correct. When calling the sd_ble_gap_rssi_start(), you will start reporting the received signal strength to the application.
A new event is reported whenever the RSSI value changes, until sd_ble_gap_rssi_stop() is called.

If you take a look at the;

uint32_t sd_ble_gap_rssi_start( 	uint16_t  	conn_handle,
		                            uint8_t  	threshold_dbm,
		                            uint8_t  	skip_count 
	) 	

You can see the threshhold_dbm parameter. That will define how big the minimum change in rssi have to be before the BLE_GAP_EVT_RSSI_CHANGED event is triggered.

And then you can use the sd_ble_gap_rssi_get() function to get the rssi for the last connection event.

Best regards,
Joakim.

[nordicdev]

Found from devzone.nordicsemi.com/.../ that the update rate for RSSISAMPLE register is the higher end of the connection interval. Sorry for the redundant question.

[Joakim Jakobsen]

Oh, I think I misunderstood what you were looking for. Glad you found out.
Best regards.