Hi,
I´m developing a BLE-OTA driver for a BLE SoC and I try to use the nRF52840 dongle with my PC as the second device for the OTA mechanism by using Python and the pc_ble_driver.py. I have an OTA service with the UUID AABBA7B0000000000000000000000501 and the service contains two characteristics for the OTA control AABBA7B0000000000000000000000604 and the OTA data AABBA7B0000000000000000000000605.
What is the correct way to send data by using the Python driver? I don´t find any example with 128-bit UUIDs, so I got stuck in the discovery and handling of these UUIDs.
import sys
import time
import logging
from queue import Queue, Empty
from pc_ble_driver_py.observers import *
global config, BLEDriver, BLEAdvData, BLEEvtID, BLEAdapter, BLEEnableParams, BLEGapTimeoutSrc, BLEUUID, BLEUUIDBase, BLEConfigCommon, BLEConfig, BLEConfigConnGatt, BLEGapScanParams
from pc_ble_driver_py import config
config.__conn_ic_id__ = "NRF52"
# noinspection PyUnresolvedReferences
from pc_ble_driver_py.ble_driver import (
BLEDriver,
BLEAdvData,
BLEEvtID,
BLEEnableParams,
BLEGapTimeoutSrc,
BLEUUID,
BLEUUIDBase,
BLEGapScanParams,
BLEConfigCommon,
BLEConfig,
BLEConfigConnGatt,
)
# noinspection PyUnresolvedReferences
from pc_ble_driver_py.ble_adapter import BLEAdapter
global nrf_sd_ble_api_ver
nrf_sd_ble_api_ver = config.sd_api_ver_get()
class OTA(BLEDriverObserver, BLEAdapterObserver):
OTA_BASE_UUID = BLEUUIDBase([0xAA, 0xBB, 0xA7, 0xCC, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0x01], 0x02)
OTA_Control_UUID = BLEUUIDBase([0xAA, 0xBB, 0xA7, 0xCC, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x04], 0x02)
OTA_Data_UUID = BLEUUIDBase([0xAA, 0xBB, 0xA7, 0xCC, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x05], 0x02)
def __init__(self, adapter):
super(OTA, self).__init__()
self.adapter = adapter
self.conn_q = Queue()
self.adapter.observer_register(self)
self.adapter.driver.observer_register(self)
self.adapter.default_mtu = 250
def open(self):
self.adapter.driver.open()
gatt_cfg = BLEConfigConnGatt()
gatt_cfg.att_mtu = self.adapter.default_mtu
gatt_cfg.tag = 1
self.adapter.driver.ble_cfg_set(BLEConfig.conn_gatt, gatt_cfg)
self.adapter.driver.ble_enable()
self.adapter.driver.ble_vs_uuid_add(OTA.OTA_BASE_UUID)
def close(self):
self.adapter.driver.close()
def connect_and_discover(self):
scan_duration = 5
params = BLEGapScanParams(interval_ms = 200, window_ms = 150, timeout_s = scan_duration)
self.adapter.driver.ble_gap_scan_start(scan_params = params)
try:
new_conn = self.conn_q.get(timeout = scan_duration)
self.adapter.service_discovery(new_conn)
return new_conn
except Empty:
print("No advertising with name 'jerry3' found.")
return None
def on_gap_evt_connected(self, ble_driver, conn_handle, peer_addr, role, conn_params):
print("New connection: {}".format(conn_handle))
self.conn_q.put(conn_handle)
def on_gap_evt_disconnected(self, ble_driver, conn_handle, reason):
print("Disconnected: {} {}".format(conn_handle, reason))
def on_gap_evt_adv_report(self, ble_driver, conn_handle, peer_addr, rssi, adv_type, adv_data):
if(BLEAdvData.Types.complete_local_name in adv_data.records):
dev_name_list = adv_data.records[BLEAdvData.Types.complete_local_name]
elif(BLEAdvData.Types.short_local_name in adv_data.records):
dev_name_list = adv_data.records[BLEAdvData.Types.short_local_name]
else:
return
dev_name = "".join(chr(e) for e in dev_name_list)
address_string = "".join("{0:02X}".format(b) for b in peer_addr.addr)
print("Received advertisment report, address: 0x{}, device_name: {}".format(address_string, dev_name))
if(dev_name == "jerry3"):
self.adapter.connect(peer_addr, tag = 1)
def on_notification(self, ble_adapter, conn_handle, uuid, data):
if(len(data) > 32):
data = "({}...)".format(data[0:10])
print("Connection: {}, {} = {}".format(conn_handle, uuid, data))
if(__name__ == "__main__"):
logging.basicConfig(level = "DEBUG", format = "%(asctime)s [%(thread)d/%(threadName)s] %(message)s")
Driver = BLEDriver(serial_port = "COM9", auto_flash = False, baud_rate = 1000000, log_severity_level = "info")
Adapter = BLEAdapter(Driver)
OTA_Handler = OTA(Adapter)
OTA_Handler.open()
Connection = OTA_Handler.connect_and_discover()
if(Connection is not None):
time.sleep(10)
while True:
nus_string = input("NUS string: ").encode()
Adapter.write_req(Connection, OTA.OTA_Control_UUID, b'a')
OTA_Handler.close()
quit()
I need to use only this service and the two characteristics because it should be a simple demonstration device for testing the OTA mechanism. Can somebody help or provide me some examples for the implementation?
Thanks and best regards
