Hello,
I'm facing a problem in pc-ble-driver-py. I adjusted the uuid_count, but the code still fails at the service discovery line:
ble_adapter.service_discovery(new_conn).
Attached is the code that searches for devices by MAC address, connects to the corresponding MAC address, initiates service discovery, and prints the data received after enabling notifications. I have two MAC addresses: one for a heart rate sensor and another for an HMI module I'm working on. Service discovery works perfectly with the heart rate sensor but fail with the HMI module. Could you please help me in identifying where I might be going wrong?
import sys
import time
from queue import Queue, Empty
from pc_ble_driver_py.ble_driver import *
from pc_ble_driver_py.ble_adapter import *
from pc_ble_driver_py.observers import *
# Constants
SERIAL_PORT = 'COM4'
BAUD_RATE = 1000000
# MAC_ADDRESS = 'F2:3A:48:56:0B:72' # mac address for heart rate sensor
MAC_ADDRESS = 'C6:C8:B9:35:FC:5D' # mac address for connected hmi
# Observer class to handle BLE events
class MyBLEDriverObserver(BLEDriverObserver, BLEAdapterObserver):
def __init__(self, adapter):
super(MyBLEDriverObserver, self).__init__()
self.found_device = False
self.conn_handle = None
self.conn_queue = Queue()
self.ble_adapter = adapter
self.ble_adapter.observer_register(self)
self.ble_adapter.driver.observer_register(self)
self.ble_adapter.default_mtu = 250
def on_gap_evt_adv_report(self, ble_driver, conn_handle, peer_addr, rssi, adv_type, adv_data):
address_string = ":".join("{0:02X}".format(b) for b in peer_addr.addr)
print(f"Found device with address: {address_string}")
if address_string == MAC_ADDRESS:
print("Attempting to connect to device...")
try:
self.found_device = True
self.ble_adapter.connect(peer_addr, tag=1)
print(f"Connection initiated to {address_string}")
except Exception as e:
print(f"Failed to connect: {str(e)}")
def on_gap_evt_connected(self, ble_driver, conn_handle, peer_addr, role, conn_params):
address_string = ":".join("{0:02X}".format(b) for b in peer_addr.addr)
print(f"Connected to {address_string}")
self.conn_handle = conn_handle
self.conn_queue.put(conn_handle)
def on_gap_evt_disconnected(self, ble_driver, conn_handle, reason):
print(f"Disconnected, reason: {reason}")
self.conn_handle = None
def on_gap_evt_timeout(self, ble_driver, conn_handle, src):
print("Connection timed out")
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))
def disconnect(self, conn_handle):
if conn_handle is not None:
self.ble_adapter.disconnect(conn_handle)
print(f"Disconnected from {MAC_ADDRESS}")
def main():
UUID_serial_number = "8E580002-3B28-4145-9213-F0646C15AB5E"
UUID_transmission_control = "6A430001-50EF-47EB-81B3-3FD7644155EC"
UUID_HeartRate_BATTERY_LEVEL = BLEUUID(BLEUUID.Standard.battery_level)
# Initialize the BLE driver
ble_driver = BLEDriver(serial_port=SERIAL_PORT, baud_rate=BAUD_RATE, log_severity_level="trace")
ble_adapter = BLEAdapter(ble_driver)
observer = MyBLEDriverObserver(ble_adapter)
ble_adapter.driver.open()
# Configuring GATT settings (MTU size)
gatt_cfg = BLEConfigConnGatt()
gatt_cfg.att_mtu = ble_adapter.default_mtu
gatt_cfg.tag = 1
ble_adapter.driver.ble_cfg_set(BLEConfig.conn_gatt, gatt_cfg)
ble_adapter.driver.ble_enable()
# Start scanning for peripherals
scan_duration = 5
scan_params = BLEGapScanParams(interval_ms=200, window_ms=150, timeout_s=scan_duration)
ble_adapter.driver.ble_gap_scan_start(scan_params=scan_params)
print("Scanning...")
# Wait for device discovery
try:
new_conn = observer.conn_queue.get(timeout=scan_duration)
print("a = ", new_conn)
a = ble_adapter.service_discovery(new_conn)
print("Device Connected")
# ble_adapter.enable_notification(new_conn, BLEUUID(UUID_serial_number))
# ble_adapter.enable_notification(new_conn, UUID_transmission_control)
# ble_adapter.enable_notification(new_conn, UUID_HeartRate_BATTERY_LEVEL)
except Empty:
print("No Device found.")
return
# Keep the program running to handle BLE events
if new_conn is not None:
try:
while True:
time.sleep(1)
except KeyboardInterrupt:
print("Keyboard Interrupt!!!")
print("Disconnecting...")
observer.disconnect(observer.conn_handle)
ble_adapter.driver.close()
if __name__ == "__main__":
main()
