def main(serial_port):
# Create and open te device
ble_device = BleDevice(serial_port)
ble_device.open()
# Create and add the Device Info Service to the database
dis = device_info.add_device_info_service(ble_device.database)
# Set some characteristics in the DIS. The service only contains characteristics which
# have values set. The other ones are not present
dis.set_software_revision("14.2.1")
dis.set_hardware_revision("A")
dis.set_firmware_revision("1.0.4")
dis.set_serial_number("AB1234")
pnp_id = device_info.PnpId(device_info.PnpVendorSource.bluetooth_sig, 0x0058, 0x0002, 0x0013)
dis.set_pnp_id(pnp_id)
# Initiate the advertising data. Advertise the name and DIS service UUID
name = "Peripheral DIS"
adv_data = advertising.AdvertisingData(local_name=name, service_uuid16s=device_info.DIS_SERVICE_UUID)
ble_device.advertiser.set_advertise_data(adv_data)
# Start advertising
logger.info("Advertising")
ble_device.client.on_connect.register(on_connect)
ble_device.client.on_disconnect.register(on_disconnect)
ble_device.advertiser.start(timeout_sec=0, auto_restart=True)
# Create a waitable that will never fire, and wait for some time
w = GenericWaitable()
w.wait(60*30, exception_on_timeout=False) # Keep device active for 30 mins
# Cleanup
logger.info("Done")
ble_device.close()
def main(serial_port):
stop_event = threading.Event()
threading.Thread(target=wait_for_user_stop, args=(stop_event, )).start()
time.sleep(2)
ble_device = BleDevice(serial_port)
ble_device.open()
interval_ms = 100 # Send out an advertising packet every 500ms
timeout_sec = 0 # Advertise forever
mode = AdvertisingMode.non_connectable_undirected # Set mode to not allow connections
adv_flags = AdvertisingFlags.BR_EDR_NOT_SUPPORTED | AdvertisingFlags.GENERAL_DISCOVERY_MODE
adv_data = AdvertisingData(flags=adv_flags,
local_name="Time",
service_data=_get_time_service_data())
ble_device.advertiser.set_advertise_data(adv_data)
ble_device.advertiser.start(interval_ms,
timeout_sec,
auto_restart=True,
advertise_mode=mode)
while True:
# Update the advertising data every 1 second
stop_event.wait(1)
if stop_event.is_set(
): # User stopped execution, break out and stop advertising
break
# Update the service data and set it in the BLE device
adv_data.service_data = _get_time_service_data()
ble_device.advertiser.set_advertise_data(adv_data)
ble_device.advertiser.stop()
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.open()
# Create and add the current time service to the database.
# Tweak the flags below to change how the service is set up
current_time_service = current_time.add_current_time_service(ble_device.database,
enable_writes=True,
enable_local_time_info=True,
enable_reference_info=False)
# Register handlers for when the characteristics are written to.
# These will only be triggered if enable_writes above is true
current_time_service.on_current_time_write.register(on_current_time_write)
current_time_service.on_local_time_info_write.register(on_local_time_info_write)
# Demo of the different ways to manually or automatically control the reported time
# Example 1: Automatically reference system time.
# All logic is handled within the service and reports the time whenever the characteristic is read
# Example 2: Manually report the time 1 day behind using callback method.
# Register a user-defined callback to retrieve the current time to report back to the client
# Example 3: Manually report the time 1 hour ahead by setting the base time
# Set the characteristic's base time to 1 day ahead and allow the service to auto-increment from there
example_mode = 1
if example_mode == 1:
# configure_automatic() also sets up the Local Time characteristic (if enabled)
# to just set the automatic time and leave Local Time unconfigured, use set_time() with no parameters
current_time_service.configure_automatic()
elif example_mode == 2:
def on_time_read():
d = datetime.datetime.now() - datetime.timedelta(days=1)
logger.info("Getting time: {}".format(d))
return d
current_time_service.set_time(characteristic_read_callback=on_time_read)
elif example_mode == 3:
base_time = datetime.datetime.now() + datetime.timedelta(hours=1)
current_time_service.set_time(base_time)
# Register listeners for when the client connects and disconnects
ble_device.client.on_connect.register(on_connect)
ble_device.client.on_disconnect.register(on_disconnect)
# Advertise the Current Time service
adv_data = advertising.AdvertisingData(local_name="Current Time", flags=0x06,
service_uuid16s=current_time.CURRENT_TIME_SERVICE_UUID)
ble_device.advertiser.set_advertise_data(adv_data)
logger.info("Advertising")
ble_device.advertiser.start(timeout_sec=0, auto_restart=True)
# Create a waitable that waits 5 minutes, then exits
w = GenericWaitable()
w.wait(5 * 60, exception_on_timeout=False)
logger.info("Done")
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.configure()
ble_device.open()
# Set up desired security parameters
ble_device.client.security.set_security_params(passcode_pairing=False, bond=False, lesc_pairing=False,
io_capabilities=IoCapabilities.DISPLAY_ONLY, out_of_band=False)
ble_device.client.security.on_pairing_complete.register(on_client_pairing_complete)
ble_device.client.security.on_passkey_display_required.register(on_passkey_display)
ble_device.client.security.on_passkey_required.register(on_passkey_entry)
ble_device.client.security.on_security_level_changed.register(on_security_level_changed)
# Create and add the math service
service = ble_device.database.add_service(constants.MATH_SERVICE_UUID)
# Create and add the hex conversion characteristic to the service
hex_conv_char = service.add_characteristic(constants.HEX_CONVERT_CHAR_UUID,
constants.HEX_CONVERT_CHAR_PROPERTIES, "Test Data")
# Register the callback for when a write occurs and subscription state changes
hex_conv_char.on_write.register(on_hex_conversion_characteristic_write)
hex_conv_char.on_subscription_change.register(on_gatts_subscription_state_changed)
# Create and add the counting characteristic, initializing the data to [0, 0, 0, 0]
counting_char = service.add_characteristic(constants.COUNTING_CHAR_UUID, constants.COUNTING_CHAR_PROPERTIES, [0]*4)
counting_char.on_subscription_change.register(on_gatts_subscription_state_changed)
# Create the thread for the counting characteristic
counting_char_thread = CountingCharacteristicThread(counting_char)
# Create and add the time service
time_service = ble_device.database.add_service(constants.TIME_SERVICE_UUID)
# Add the time characteristic and register the callback for when its read
time_char = time_service.add_characteristic(constants.TIME_CHAR_UUID, constants.TIME_CHAR_PROPERTIES, "Time")
time_char.on_read.register(on_time_char_read)
# Initialize the advertising and scan response data
adv_data = advertising.AdvertisingData(local_name=constants.PERIPHERAL_NAME, flags=0x06)
scan_data = advertising.AdvertisingData(service_uuid128s=constants.TIME_SERVICE_UUID, has_more_uuid128_services=True)
ble_device.advertiser.set_advertise_data(adv_data, scan_data)
# Start advertising
logger.info("Advertising")
ble_device.client.on_connect.register(on_connect)
ble_device.client.on_disconnect.register(on_disconnect)
ble_device.advertiser.start(timeout_sec=0, auto_restart=True)
# Create a waitable that will never fire, and wait for some time
w = GenericWaitable()
w.wait(60*30, exception_on_timeout=False) # Keep device active for 30 mins
# Cleanup
counting_char_thread.join()
logger.info("Done")
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.open()
# Create a database to store the readings
glucose_database = glucose.BasicGlucoseDatabase()
# Add the service to the BLE database, using the glucose database just created, require encryption at the minimum
service = glucose.add_glucose_service(ble_device.database,
glucose_database,
glucose.SecurityLevel.JUST_WORKS)
# Set the features of this "glucose sensor"
features = glucose.GlucoseFeatures(
GlucoseFeatureType.low_battery_detection,
GlucoseFeatureType.strip_insertion_error_detection)
service.set_features(features)
# Add some measurements to the glucose database
add_fake_glucose_readings(glucose_database)
# Register listeners for when the client connects and disconnects
ble_device.client.on_connect.register(on_connect)
ble_device.client.on_disconnect.register(on_disconnect)
# Set the connection parameters for the client
ble_device.client.set_connection_parameters(15, 30, 4000)
# Set the function to display the passkey
ble_device.client.security.on_passkey_display_required.register(
display_passkey)
# Set the security parameters for the client
ble_device.client.security.set_security_params(
passcode_pairing=False,
bond=False,
io_capabilities=IoCapabilities.DISPLAY_ONLY,
out_of_band=False)
# Advertise the Glucose service
adv_data = advertising.AdvertisingData(
local_name="Glucose Test",
flags=0x06,
service_uuid16s=glucose.GLUCOSE_SERVICE_UUID)
ble_device.advertiser.set_advertise_data(adv_data)
logger.info("Advertising")
ble_device.advertiser.start(timeout_sec=0, auto_restart=True)
# Create a waitable that will never fire, and wait for some time
w = GenericWaitable()
w.wait(60 * 30,
exception_on_timeout=False) # Keep device active for 30 mins
logger.info("Done")
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.open()
logger.info("Scanning...")
# Set scanning for 4 seconds
ble_device.scanner.set_default_scan_params(timeout_seconds=4)
# Start scanning and wait for it to complete
scan_report = ble_device.scanner.start_scan().wait()
print("")
logger.info("Finished scanning. Scan reports:")
# Iterate through all the peers found and print out the reports
for report in scan_report.advertising_peers_found:
logger.info(report)
# Clean up and close the device
ble_device.close()
def main(serial_port):
ble_device = BleDevice(serial_port)
# Configure the BLE device to support MTU sizes which allow the max data length extension PDU size
# Note this isn't 100% necessary as the default configuration sets the max to this value also
ble_device.configure(att_mtu_max_size=MTU_SIZE_FOR_MAX_DLE)
ble_device.open()
# Create and add the Nordic UART service
nus = nordic_uart.add_nordic_uart_service(ble_device.database)
nus.on_data_received.register(on_data_rx)
nus.on_write_complete.register(on_tx_complete)
# Register listeners for when the client connects and disconnects
ble_device.client.on_connect.register(on_connect)
ble_device.client.on_disconnect.register(on_disconnect)
ble_device.client.on_mtu_size_updated.register(on_mtu_size_update)
# Configure the client to prefer the max MTU size
ble_device.client.preferred_mtu_size = ble_device.max_mtu_size
ble_device.client.set_connection_parameters(7.5, 15, 4000)
# Advertise the service UUID
adv_data = advertising.AdvertisingData(flags=0x06,
local_name="Nordic UART Server")
scan_data = advertising.AdvertisingData(
service_uuid128s=nordic_uart.NORDIC_UART_SERVICE_UUID)
ble_device.advertiser.set_advertise_data(adv_data, scan_data)
logger.info("Advertising")
ble_device.advertiser.start(timeout_sec=0, auto_restart=True)
# Create a waitable that waits 5 minutes then exits
w = GenericWaitable()
try:
w.wait(5 * 60, exception_on_timeout=False)
except KeyboardInterrupt:
pass
finally:
ble_device.close()
def main(serial_port):
target_device_name = constants.PERIPHERAL_NAME
# Create a waitable that will block the main thread until notified by one of the classes above
main_thread_waitable = GenericWaitable()
# Create and open the BLE device (and suppress spammy logs)
ble_device = BleDevice(serial_port)
ble_device.event_logger.suppress(nrf_events.GapEvtAdvReport)
ble_device.open()
# Create the connection manager and start the scanning process
s = ConnectionManager(ble_device, main_thread_waitable)
s.scan_and_connect(target_device_name)
# Block the main thread indefinitely until the program finishes
main_thread_waitable.wait()
# Clean up, disconnect if a peer was connected to
if s.peer:
s.peer.disconnect().wait()
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.open()
# Create and add the battery service to the database
battery_service = battery.add_battery_service(ble_device.database,
enable_notifications=True)
battery_service.set_battery_level(100, False)
# Register listeners for when the client connects and disconnects
ble_device.client.on_connect.register(on_connect)
ble_device.client.on_disconnect.register(on_disconnect)
# Leaving security and connection parameters as defaults (don't care)
# Advertise the Battery Service
adv_data = advertising.AdvertisingData(
local_name="Battery Test",
flags=0x06,
service_uuid16s=battery.BATTERY_SERVICE_UUID)
ble_device.advertiser.set_advertise_data(adv_data)
logger.info("Advertising")
ble_device.advertiser.start(timeout_sec=0, auto_restart=True)
battery_level = 100
battery_level_decrement_steps = 1
time_between_steps = 10
# Decrement the battery level until it runs out
while battery_level >= 0:
time.sleep(time_between_steps)
battery_level -= battery_level_decrement_steps
logger.info("Updating battery level to {}".format(battery_level))
battery_service.set_battery_level(battery_level)
logger.info("Done")
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.open()
logger.info("Scanning...")
# Set scanning for 4 seconds
ble_device.scanner.set_default_scan_params(timeout_seconds=4)
# Start scanning and iterate through the reports as they're received
for report in ble_device.scanner.start_scan().scan_reports:
if not report.duplicate:
logger.info(report)
scan_report = ble_device.scanner.scan_report
print("\n")
logger.info("Finished scanning. Scan reports by peer address:")
# Iterate through all the peers found and print out the reports
for report in scan_report.advertising_peers_found:
logger.info(report)
# Clean up and close the device
ble_device.close()
def main(serial_port):
# Open the BLE Device and suppress spammy log messages
ble_device = BleDevice(serial_port)
ble_device.event_logger.suppress(nrf_events.GapEvtAdvReport)
# Configure the BLE device to support MTU sizes which allow the max data length extension PDU size
# Note this isn't 100% necessary as the default configuration sets the max to this value also
ble_device.configure(att_mtu_max_size=MTU_SIZE_FOR_MAX_DLE)
ble_device.open()
# Set scan duration for 4 seconds
ble_device.scanner.set_default_scan_params(timeout_seconds=4)
ble_device.set_default_peripheral_connection_params(10, 30, 4000)
logger.info("Scanning for peripherals advertising UUID {}".format(
nordic_uart.NORDIC_UART_SERVICE_UUID))
target_address = None
# Start scan and wait for it to complete
scan_report = ble_device.scanner.start_scan().wait()
# Search each peer's advertising data for the Nordic UART Service UUID to be advertised
for report in scan_report.advertising_peers_found:
if nordic_uart.NORDIC_UART_SERVICE_UUID in report.advertise_data.service_uuid128s and report.device_name == "Nordic UART Server":
target_address = report.peer_address
break
if not target_address:
logger.info("Did not find peripheral advertising Nordic UART service")
return
# Initiate connection and wait for it to finish
logger.info("Found match: connecting to address {}".format(target_address))
peer = ble_device.connect(target_address).wait()
if not peer:
logger.warning("Timed out connecting to device")
return
logger.info("Connected, conn_handle: {}".format(peer.conn_handle))
logger.info("Exchanging MTU")
peer.exchange_mtu(peer.max_mtu_size).wait(10)
logger.info("MTU Exchange complete, discovering services")
# Initiate service discovery and wait for it to complete
_, event_args = peer.discover_services().wait(exception_on_timeout=False)
logger.info("Service discovery complete! status: {}".format(
event_args.status))
uart_service = nordic_uart.find_nordic_uart_service(peer.database)
if not uart_service:
logger.info(
"Failed to find Nordic UART service in peripheral database")
peer.disconnect().wait()
ble_device.close()
return
# Initialize the service
uart_service.initialize().wait(5)
uart_service.on_data_received.register(on_data_rx)
while True:
data = input("Enter data to send to peripheral (q to exit): ")
if data == "q":
break
uart_service.write(data).wait(10)
peer.disconnect().wait()
ble_device.close()
def main(serial_port):
# Set the target to the peripheral's advertised name
target_device_name = constants.PERIPHERAL_NAME
# Create and open the BLE device (and suppress spammy logs)
ble_device = BleDevice(serial_port)
ble_device.event_logger.suppress(nrf_events.GapEvtAdvReport)
ble_device.open()
# Set the scanner to scan for 4 seconds
ble_device.scanner.set_default_scan_params(timeout_seconds=4)
logger.info("Scanning for '{}'".format(target_device_name))
target_address = example_utils.find_target_device(ble_device, target_device_name)
if not target_address:
logger.info("Did not find target peripheral")
return
# Initiate the connection and wait for it to finish
logger.info("Found match: connecting to address {}".format(target_address))
peer = ble_device.connect(target_address).wait()
if not peer:
logger.warning("Timed out connecting to device")
return
# Wait up to 10 seconds for service discovery to complete
logger.info("Connected, conn_handle: {}".format(peer.conn_handle))
_, event_args = peer.discover_services().wait(10, exception_on_timeout=False)
logger.info("Service discovery complete! status: {}".format(event_args.status))
# Log each service found
for service in peer.database.services:
logger.info(service)
peer.set_connection_parameters(100, 120, 6000) # Discovery complete, go to a longer connection interval
# Pair with the peripheral
def on_passkey_entry(peer, passkey_event_args):
"""
Callback for when the user is requested to enter a passkey to resume the pairing process.
Requests the user to enter the passkey and resolves the event with the passkey entered
:param peer: the peer the passkey is for
:param passkey_event_args:
:type passkey_event_args: blatann.event_args.PasskeyEntryEventArgs
"""
passkey = input("Enter peripheral passkey: ")
passkey_event_args.resolve(passkey)
# Setup the security parameters
peer.security.set_security_params(passcode_pairing=True, io_capabilities=smp.IoCapabilities.KEYBOARD_DISPLAY,
bond=False, out_of_band=False)
# Register the callback for when a passkey needs to be entered by the user
peer.security.on_passkey_required.register(on_passkey_entry)
# Wait up to 60 seconds for the pairing process
peer.security.pair().wait(60)
# Find the counting characteristic
counting_char = peer.database.find_characteristic(constants.COUNTING_CHAR_UUID)
if counting_char:
logger.info("Subscribing to the counting characteristic")
counting_char.subscribe(on_counting_char_notification).wait(5)
else:
logger.warning("Failed to find counting characteristic")
# Find the hex conversion characteristic. This characteristic takes in a bytestream and converts it to its
# hex representation. e.g. '0123' -> '30313233'
hex_convert_char = peer.database.find_characteristic(constants.HEX_CONVERT_CHAR_UUID)
if hex_convert_char:
# Generate some data ABCDEFG... Then, incrementally send increasing lengths of strings.
# i.e. first send 'A', then 'AB', then 'ABC'...
data_to_convert = bytes(ord('A') + i for i in range(12))
for i in range(len(data_to_convert)):
data_to_send = data_to_convert[:i+1]
logger.info("Converting to hex data: '{}'".format(data_to_send))
# Write the data, waiting up to 5 seconds for the write to complete
if not hex_convert_char.write(data_to_send).wait(5, False):
logger.error("Failed to write data, i={}".format(i))
break
# Write was successful, when we read the characteristic the peripheral should have converted the string
# Once again, initiate a read and wait up to 5 seconds for the read to complete
char, event_args = hex_convert_char.read().wait(5, False)
logger.info("Hex: '{}'".format(event_args.value.decode("ascii")))
else:
logger.warning("Failed to find hex convert char")
# Clean up
logger.info("Disconnecting from peripheral")
peer.disconnect().wait()
ble_device.close()
def main(serial_port):
# Open the BLE Device and suppress spammy log messages
ble_device = BleDevice(serial_port)
ble_device.event_logger.suppress(nrf_events.GapEvtAdvReport)
ble_device.open()
# Set scan duration to 4 seconds
ble_device.scanner.set_default_scan_params(timeout_seconds=4)
logger.info("Scanning for peripherals advertising UUID {}".format(
device_info.DIS_SERVICE_UUID))
target_address = None
# Start scan and wait for it to complete
scan_report = ble_device.scanner.start_scan().wait()
# Search each peer's advertising data for the DIS Service UUID to be advertised
for report in scan_report.advertising_peers_found:
if device_info.DIS_SERVICE_UUID in report.advertise_data.service_uuid16s:
target_address = report.peer_address
break
if not target_address:
logger.info("Did not find peripheral advertising DIS service")
return
# Initiate connection and wait for it to finish
logger.info("Found match: connecting to address {}".format(target_address))
peer = ble_device.connect(target_address).wait()
if not peer:
logger.warning("Timed out connecting to device")
return
logger.info("Connected, conn_handle: {}".format(peer.conn_handle))
# Initiate service discovery and wait for it to complete
_, event_args = peer.discover_services().wait(10,
exception_on_timeout=False)
logger.info("Service discovery complete! status: {}".format(
event_args.status))
# Find the device info service in the peer's database
dis = device_info.find_device_info_service(peer.database)
if not dis:
logger.info(
"Failed to find Device Info Service in peripheral database")
peer.disconnect().wait()
return
# Example 1:
# Iterate through all possible device info characteristics, read the value if present in service
for char in device_info.CHARACTERISTICS:
if dis.has(char):
logger.info("Reading characteristic: {}...".format(char))
char, event_args = dis.get(char).wait()
if isinstance(event_args.value, bytes):
value = event_args.value.decode("utf8")
else:
value = event_args.value
logger.info("Value: {}".format(value))
# Example 2:
# Read specific characteristics, if present in the service
if dis.has_software_revision:
char, event_args = dis.get_software_revision().wait()
sw_version = event_args.value
logger.info("Software Version: {}".format(sw_version.decode("utf8")))
if dis.has_pnp_id:
char, event_args = dis.get_pnp_id().wait()
pnp_id = event_args.value # type: device_info.PnpId
logger.info("Vendor ID: {}".format(pnp_id.vendor_id))
if dis.has_system_id:
char, event_args = dis.get_system_id().wait()
system_id = event_args.value # type: device_info.SystemId
logger.info("System ID: {}".format(system_id))
# Disconnect and close device
peer.disconnect().wait()
ble_device.close()
def main(serial_port):
# Open the BLE Device and suppress spammy log messages
ble_device = BleDevice(serial_port)
ble_device.event_logger.suppress(nrf_events.GapEvtAdvReport)
ble_device.open()
# Set scan duration for 4 seconds
ble_device.scanner.set_default_scan_params(timeout_seconds=4)
logger.info("Scanning for peripherals advertising UUID {}".format(
battery.BATTERY_SERVICE_UUID))
target_address = None
# Start scan and wait for it to complete
scan_report = ble_device.scanner.start_scan().wait()
# Search each peer's advertising data for the Battery Service UUID to be advertised
for report in scan_report.advertising_peers_found:
if battery.BATTERY_SERVICE_UUID in report.advertise_data.service_uuid16s:
target_address = report.peer_address
break
if not target_address:
logger.info("Did not find peripheral advertising battery service")
return
# Initiate connection and wait for it to finish
logger.info("Found match: connecting to address {}".format(target_address))
peer = ble_device.connect(target_address).wait()
if not peer:
logger.warning("Timed out connecting to device")
return
logger.info("Connected, conn_handle: {}".format(peer.conn_handle))
# Initiate service discovery and wait for it to complete
_, event_args = peer.discover_services().wait(10,
exception_on_timeout=False)
logger.info("Service discovery complete! status: {}".format(
event_args.status))
# Find the battery service within the peer's database
battery_service = battery.find_battery_service(peer.database)
if not battery_service:
logger.info("Failed to find Battery Service in peripheral database")
peer.disconnect().wait()
return
# Read out the battery level
logger.info("Reading battery level...")
_, event_args = battery_service.read().wait()
battery_percent = event_args.value
logger.info("Battery: {}%".format(battery_percent))
if battery_service.can_enable_notifications:
battery_service.on_battery_level_updated.register(
on_battery_level_update)
battery_service.enable_notifications().wait()
wait_duration = 30
logger.info("Waiting {} seconds for any battery notifications")
time.sleep(wait_duration)
# Clean up
logger.info("Disconnecting from peripheral")
peer.disconnect().wait()
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.configure()
ble_device.open()
# Create the service
service = ble_device.database.add_service(
constants.DESC_EXAMPLE_SERVICE_UUID)
# Create a characteristic and add some descriptors
# NOTE: Some descriptors MUST be added during creation: SCCD, User Description, and Presentation Format
# CCCD is added automatically based on the characteristic's Notify and Indicate properties
# Define the User Description properties and make it writable
# The simplest use-case in which the user description is read-only can provide just the first parameter
user_desc_props = gatts.GattsUserDescriptionProperties(
"UTC Time",
write=True,
security_level=smp.SecurityLevel.OPEN,
max_length=20,
variable_length=True)
# Define the presentation format. Returning the time in seconds so set exponent to 0
presentation_format = PresentationFormat(fmt=Format.uint32,
exponent=0,
unit=Units.time_second)
# Create the characteristic properties, including the SCCD, User Description, and Presentation Format
char_props = gatts.GattsCharacteristicProperties(
read=True,
write=False,
notify=True,
max_length=Uint32.byte_count,
variable_length=False,
sccd=True,
user_description=user_desc_props,
presentation_format=presentation_format)
char = service.add_characteristic(constants.DESC_EXAMPLE_CHAR_UUID,
char_props, Uint32.encode(0))
char.on_read.register(on_read)
# Add another descriptor to the list
char_range_value = Uint32.encode(5555) + Uint32.encode(2**32 - 1000)
desc_props = GattsAttributeProperties(read=True,
write=False,
variable_length=False,
max_length=len(char_range_value))
char.add_descriptor(DescriptorUuid.valid_range, desc_props,
char_range_value)
# Initialize the advertising and scan response data
adv_data = advertising.AdvertisingData(
local_name=constants.PERIPHERAL_NAME, flags=0x06)
scan_data = advertising.AdvertisingData(
service_uuid128s=constants.DESC_EXAMPLE_SERVICE_UUID,
has_more_uuid128_services=False)
ble_device.advertiser.set_advertise_data(adv_data, scan_data)
# Start advertising
logger.info("Advertising")
ble_device.client.on_connect.register(on_connect)
ble_device.client.on_disconnect.register(on_disconnect)
ble_device.advertiser.start(timeout_sec=0, auto_restart=True)
# Create a waitable that will never fire, and wait for some time
w = GenericWaitable()
w.wait(60 * 30,
exception_on_timeout=False) # Keep device active for 30 mins
logger.info("Done")
ble_device.close()
def main(serial_port):
# Create and open the device
ble_device = BleDevice(serial_port)
ble_device.configure()
ble_device.open()
ble_device.scanner.set_default_scan_params(timeout_seconds=4)
# Set the target to the peripheral's advertised name
target_device_name = constants.PERIPHERAL_NAME
logger.info("Scanning for '{}'".format(target_device_name))
target_address = example_utils.find_target_device(ble_device, target_device_name)
if not target_address:
logger.info("Did not find target peripheral")
return
# Initiate the connection and wait for it to finish
logger.info("Found match: connecting to address {}".format(target_address))
peer = ble_device.connect(target_address).wait()
if not peer:
logger.warning("Timed out connecting to device")
return
logger.info("Connected, conn_handle: {}".format(peer.conn_handle))
# Wait up to 10 seconds for service discovery to complete
_, event_args = peer.discover_services().wait(10, exception_on_timeout=False)
logger.info("Service discovery complete! status: {}".format(event_args.status))
# Find the Time characteristic
time_char = peer.database.find_characteristic(constants.DESC_EXAMPLE_CHAR_UUID)
if not time_char:
logger.info("Did not find the time characteristic")
else:
logger.info("Reading all characteristic attributes")
for attr in time_char.attributes:
logger.info(f"Reading UUID {attr.uuid} - {attr.uuid.description or '[unknown]'}")
_, event_args = attr.read().wait(5)
if event_args.status == GattStatusCode.success:
# Show as hex unless it's the user descriptor UUID which should be a string
if attr.uuid == DescriptorUuid.user_description:
value = event_args.value.decode("utf8")
else:
value = binascii.hexlify(event_args.value)
logger.info(f" Value: {value}")
else:
logger.warning(f" Failed to read attribute, status: {event_args.status}")
# Read the characteristic's Presentation Format descriptor directly and decode the value
presentation_fmt_desc = time_char.find_descriptor(DescriptorUuid.presentation_format)
if presentation_fmt_desc:
# Read, then decode the value using the PresentationFormat type
logger.info("Reading the presentation format descriptor directly")
_, event_args = presentation_fmt_desc.read().wait(5)
if event_args.status == GattStatusCode.success:
try:
fmt = PresentationFormat.decode(event_args.value)
logger.info(f"Presentation Format: {str(fmt.format)}, Exponent: {fmt.exponent}, Unit: {str(fmt.unit)}")
except Exception as e:
logger.error("Failed to decode the presentation format descriptor")
logger.exception(e)
else:
logger.info("Failed to find the presentation format descriptor")
# Clean up
logger.info("Disconnecting from peripheral")
peer.disconnect().wait()
ble_device.close()