def from_bytes(cls, data):
if len(data) < 3:
raise Exception('invalid data (size)')
if data[0] != 0x40 and data[0] != 0x4f:
raise Exception('invalid start byte')
tableid = struct.unpack('>H', data[1:3])[0]
chksum = data[-1]
if data[0] == 0x40:
table_data = data[5:-1]
offset = None
elif data[0] == 0x4f:
table_data = data[8:-1]
offset = struct.unpack('>I', b'\x00' + data[3:6])[0]
if check_data_checksum(table_data, chksum):
raise Exception('invalid check sum')
request = cls(tableid, table_data, offset=offset)
request.write = data[0]
return request
def from_bytes(cls, data):
if len(data) < 3:
raise Exception('invalid data (size)')
if data[0] != 0x40 and data[0] != 0x4f:
raise Exception('invalid start byte')
tableid = struct.unpack('>H', data[1:3])[0]
chksum = data[-1]
if data[0] == 0x40:
table_data = data[5:-1]
offset = None
elif data[0] == 0x4f:
table_data = data[8:-1]
offset = struct.unpack('>I', b'\x00' + data[3:6])[0]
if check_data_checksum(table_data, chksum):
raise Exception('invalid check sum')
request = cls(tableid, table_data, offset=offset)
request.write = data[0]
return request
def parse(data):
if len(data) < 3:
raise Exception('invalid data (size)')
if data[0] != b'\x40' and data[0] != b'\x4f':
raise Exception('invalid start byte')
tableid = struct.unpack('>H', data[1:3])[0]
chksum = data[-1]
if data[0] == b'\x40':
table_data = data[5:-1]
offset = None
elif data[0] == b'\x4f':
table_data = data[8:-1]
offset = struct.unpack('>I', b'\x00' + data[3:6])[0]
if check_data_checksum(table_data, chksum):
raise Exception('invalid check sum')
request = C1218WriteRequest(tableid, table_data, offset=offset)
request.write = data[0]
return request
def get_table_data(self, tableid, octetcount=None, offset=None):
#print("\n\n\n***connection.py-564 : Inside get table data****\n\n\n")
"""
Read data from a table. If successful, all of the data from the
requested table will be returned.
:param int tableid: The table number to read from (0x0000 <= tableid <= 0xffff)
:param int octetcount: Limit the amount of data read, only works if
the meter supports this type of reading.
:param int offset: The offset at which to start to read the data from.
"""
#print("\n\n\n***Table ID: {}****\n\n\n".format(tableid))
if self.caching_enabled and tableid in self._cacheable_tables and tableid in self._table_cache.keys():
self.logger.info('returning cached table #' + str(tableid))
return self._table_cache[tableid]
self.send(C1218ReadRequest(tableid, offset, octetcount))
data = self.recv()
status = data[0]
if status != 0x00:
status = status
details = (C1218_RESPONSE_CODES.get(status) or 'unknown response code')
self.logger.error('could not read table id: ' + str(tableid) + ', error: ' + details)
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: ' + details, status)
if len(data) < 4:
if len(data) == 0:
self.logger.error('could not read table id: ' + str(tableid) + ', error: no data was returned')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: no data was returned')
self.logger.error('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length (less than 4)')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length (less than 4)')
length = struct.unpack('>H', data[1:3])[0]
chksum = data[-1]
data = data[3:-1]
if len(data) != length:
self.logger.error('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length')
if not check_data_checksum(data, chksum):
self.logger.error('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid check sum')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid checksum')
if self.caching_enabled and tableid in self._cacheable_tables and not tableid in self._table_cache.keys():
self.logger.info('caching table #' + str(tableid))
self._table_cache[tableid] = data
#print("\n\n\n***End of get_table_data****\n\n\n")
return data
def get_table_data(self, tableid, octetcount=None, offset=None):
"""
Read data from a table. If successful, all of the data from the
requested table will be returned.
:param int tableid: The table number to read from (0x0000 <= tableid <= 0xffff)
:param int octetcount: Limit the amount of data read, only works if
the meter supports this type of reading.
:param int offset: The offset at which to start to read the data from.
"""
if self.caching_enabled and tableid in self.__cacheable_tbls__ and tableid in self.__tbl_cache__.keys():
self.logger.info('returning cached table #' + str(tableid))
return self.__tbl_cache__[tableid]
self.send(C1218ReadRequest(tableid, offset, octetcount))
data = self.recv()
status = data[0]
if status != 0x00:
status = status
details = (C1218_RESPONSE_CODES.get(status) or 'unknown response code')
self.logger.error('could not read table id: ' + str(tableid) + ', error: ' + details)
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: ' + details, status)
if len(data) < 4:
if len(data) == 0:
self.logger.error('could not read table id: ' + str(tableid) + ', error: no data was returned')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: no data was returned')
self.logger.error('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length (less than 4)')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length (less than 4)')
length = struct.unpack('>H', data[1:3])[0]
chksum = data[-1]
data = data[3:-1]
if len(data) != length:
self.logger.error('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid length')
if not check_data_checksum(data, chksum):
self.logger.error('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid check sum')
raise C1218ReadTableError('could not read table id: ' + str(tableid) + ', error: data read was corrupt, invalid checksum')
if self.caching_enabled and tableid in self.__cacheable_tbls__ and not tableid in self.__tbl_cache__.keys():
self.logger.info('caching table #' + str(tableid))
self.__tbl_cache__[tableid] = data
return data
