How to select Packet type in pc-ble-driver-py and to switch between scan and adv mode

[Yahya Tawil]

Hello

I used the pc-ble-driver-py to advertise Apple ibeacons, but it seems that they're advertised as connectable undirected packets which is not good in my case, as I filter in NRF52 firmware packets based on packet type (1- not scan response 2- not connectable packet).

ble_gap_adv_start() method do have adv_params argument but it's just for interval and timeout. while the packet type is specified as following (I think)

    def ble_gap_adv_start(self, adv_params=None):
        if not adv_params:
            adv_params = self.adv_params_setup()
        assert isinstance(adv_params, BLEGapAdvParams), 'Invalid argument type'
        return driver.sd_ble_gap_adv_start(self.rpc_adapter, adv_params.to_c())

....

    def to_c(self):
        adv_params              = driver.ble_gap_adv_params_t()
        adv_params.type         = BLEGapAdvType.connectable_undirected.value
        adv_params.p_peer_addr  = None  # Undirected advertisement.
        adv_params.fp           = driver.BLE_GAP_ADV_FP_ANY
        adv_params.p_whitelist  = None
        adv_params.interval     = util.msec_to_units(self.interval_ms,
                                                                util.UNIT_0_625_MS)
        adv_params.timeout      = self.timeout_s

My other question is regards how to switch between scan and adv in pc-ble-driver-py. When I do setup like:

self.driver      = BLEDriver(serial_port=self.serial_port, auto_flash=False)
self.driver.observer_register(self)
self.adapter.driver.observer_register(self)
self.driver.open()
self.driver.ble_enable()

When I do scan alone it works, and when I do adv alone it works, but when the same program change from scan<->adv based on same setup, I get errors like

pc_ble_driver_py.exceptions.NordicSemiException: Failed to ble_gap_adv_start. Error code: 18

or can't start scan according to switch case.

[Jørgen Holmefjord]

Hi,

I'm not sure that I understand your first question. Are you asking if this is the correct way of defining packet type? Have you tested if it works?

Regarding your second question, which version of pc-ble-driver-py are you using, and on which chip? Error code 18 typically means NRF_ERROR_CONN_COUNT, which indicate that you have reached the number of allowed connections and that advertising can therefore not be started.

Best regards,
Jørgen

[Yahya Tawil]

Hello Jørgen

First question was to know how to switch advertised packet type between connectable and non-connectable ?
Yes, I can advertise correctly but I don't want the advertisements to be connectable

Regards, the second question .. I start with adv/scan and then switch to the scan/adv and get Failed to ble_gap_adv/scan_start

            self.driver      = BLEDriver(serial_port="COM8", auto_flash=False)
            adv_data    = BLEAdvData(flags=flags_data,manufacturer_specific_data=manu_data)
            self.driver.observer_register(self)
            self.adapter.driver.observer_register(self)
            self.driver.open()
            self.driver.ble_enable()
            self.driver.ble_gap_adv_data_set(adv_data)
            self.driver.ble_gap_adv_start()
            time.sleep(2)
            self.driver.ble_gap_adv_stop()
            time.sleep(4)
            self.adapter.driver.ble_gap_scan_start() #here I get the error failed to start scan
            

I have pc-ble-driver-py 0.11.4 with connectivity_1.2.0_115k2_with_s132_3.0.hex and nrf52 dev kit.