gap_set_scan_params() function
Set parameters for LE Scan
Arguments
scan_type
0 = passive, 1 = active
scan_interval
range 0x0004..0x4000, unit 0.625 ms
scan_window
range 0x0004..0x4000, unit 0.625 ms
scanning_filter_policy
0 = all devices, 1 = all from whitelist