def read_single_value(self, address, additional_data="1"):
"""
Reads a value from an address in the device.
:param address:
:param additional_data:
:return:
"""
# TODO Can't find documentation on why the additional_data of 1 is needed.
# LIS-200 Specific?
# TODO: When not using the additional data on an EMH meter we get an ack back.
# a bit later we get the break message. Is the device waiting?
request = messages.CommandMessage.for_single_read(
address, additional_data)
logger.info(f"Sending read request: {request}")
self.transport.send(request.to_bytes())
response = self.read_response()
if len(response.data) > 1:
raise exceptions.TooManyValuesReturned(
f"Read of one value returned {len(response.data)}")
if len(response.data) == 0:
raise exceptions.NoDataReturned(f"Read returned no data")
logger.info(f"Received response: {response}")
# Just return the data, not in a list since it is just one.
return response.data[0]
def read_multi_value(self, address, additional_data=""):
"""
Reads a value from an address in the device.
:param address:
:param additional_data:
:return:
"""
# TODO Can't find documentation on why the additional_data of 1 is needed.
request = messages.CommandMessage.for_single_read(
address, additional_data)
logger.info(f"Sending read request: {request}")
self.transport.send(request.to_bytes())
response = self.read_response()
if len(response.data) == 0:
raise exceptions.NoDataReturned(f"Read returned no data")
logger.info(f"Received response: {response}")
# Just return the data, not in a list since it is just one.
return response.data