def parse_response(self, response):
"""Extract the pdu from the Modbus RTU response"""
#if len(response) < 3:
#raise ModbusInvalidResponseError("Response length is invalid {0}".format(len(response)))
(self._response_address, ) = struct.unpack(">B", response[0:1])
if self._request_address != self._response_address:
raise ModbusInvalidResponseError(
"Response address {0} is different from request address {1}".
format(self._response_address, self._request_address))
(crc, ) = struct.unpack(">H", response[-2:])
if crc != utils.calculate_crc(response[:-2]):
raise ModbusInvalidResponseError("Invalid CRC in response")
return response[1:-2]
def parse_response(self, response):
"""Extract the pdu from the Modbus TCP response"""
if len(response) > 6:
mbap, pdu = response[:7], response[7:]
self._response_mbap.unpack(mbap)
self._response_mbap.check_response(self._request_mbap, len(pdu))
return pdu
else:
raise ModbusInvalidResponseError("Response length is only {0} bytes. ".format(len(response)))