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

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

Yahya Tawil — Wed, 03 Apr 2019 17:31:35 GMT

Thanks Jorgen

I already did that as a change inside the driver, but it will be very helpful to add this option originally in your package.

About the other problem, There is no special reason behind that, I will try using the other way soon and let you know if could solve it.

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

Jørgen Holmefjord — Wed, 03 Apr 2019 15:25:51 GMT

Yes, you can change the advertising type there, but you can also extend the driver with a parameter for type in BLEGapAdvParams, that can be configured in the application:

class BLEGapAdvParams(object):
    def __init__(self, interval_ms, timeout_s, adv_type):
        self.interval_ms    = interval_ms
        self.timeout_s      = timeout_s
        self.adv_type       = adv_type


    def to_c(self):
        adv_params              = driver.ble_gap_adv_params_t()
        adv_params.type         = self.adv_type
        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

        return adv_params

You would then also have to modify the setup function:

    def adv_params_setup(self):
        return BLEGapAdvParams(interval_ms = 40,
                               timeout_s   = 180,
							   adv_type    = BLEGapAdvType.connectable_undirected.value)

It should then be possible to set the type directly in the application (this is from modified advertising.py example):

def init(conn_ic_id):
    global BLEDriver, BLEAdvData, BLEEvtID, BLEGapAdvParams, BLEGapAdvType
    from pc_ble_driver_py import config
    config.__conn_ic_id__ = conn_ic_id
    from pc_ble_driver_py.ble_driver    import BLEDriver, BLEAdvData, BLEEvtID, BLEGapAdvParams, BLEGapAdvType

def main(serial_port):
    print("Serial port used: {}".format(serial_port))
    driver      = BLEDriver(serial_port=serial_port, auto_flash=True)
    observer    = TimeoutObserver()
    adv_data    = BLEAdvData(complete_local_name='Example')
    adv_params  = BLEGapAdvParams(interval_ms=40, timeout_s=180, adv_type=BLEGapAdvType.non_connectable_undirected)

    driver.observer_register(observer)
    driver.open()
    driver.ble_enable()
    driver.ble_gap_adv_data_set(adv_data)
    driver.ble_gap_adv_start()
    observer.wait_for_timeout()

    print("Closing")
    driver.close()

Is there any specific reason that you start scanning with 'self.adapter.driver.ble_gap_scan_start()' and not 'self.driver.ble_gap_scan_start()'? I think this will call functions directly in the C library.

Best regards,
Jørgen

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

Yahya Tawil — Wed, 03 Apr 2019 14:15:25 GMT

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.

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

Jørgen Holmefjord — Wed, 03 Apr 2019 13:47:51 GMT

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