class LogixDriverCOMServer:
_reg_clsctx_ = pythoncom.CLSCTX_LOCAL_SERVER
_public_methods_ = ['open', 'close', 'read_tag', 'write', ] #'get_plc_info', 'get_plc_name', 'get_tag_list']
_readonlu_attrs_ = []
_public_attrs_ = []
# _readonly_attrs_ = ['tags', 'info', 'name']
# _public_attrs_ = ['path', 'large_packets', 'init_tags', 'init_program_tags' ] + _readonly_attrs_
_reg_clsid_ = CLSID
_reg_desc_ = 'Pycomm3 - Python Ethernet/IP ControlLogix Library COM Server'
_reg_progid_ = 'Pycomm3.COMServer'
def __init__(self):
self.plc: LogixDriver = None
def open(self, path, init_tags=True, init_program_tags=False, init_info=True):
self.plc = LogixDriver(path, init_tags=init_tags, init_program_tags=init_program_tags, init_info=init_info)
self.plc.open()
def close(self):
self.plc.close()
def read(self, tag):
result = self.plc.read(tag)
return result.value if result else None
def write(self, *tag_values):
return self.plc.write(*tag_values)
def read():
try:
plc_path = request.args.get('plc')
tag = request.args.get('tag')
if plc_path in plc_connections.keys():
plc = plc_connections[plc_path]
else:
plc = LogixDriver(plc_path)
plc_connections[plc_path] = plc
val = plc.read(tag).value
return jsonify({'status': 'success', 'val': val})
except:
import traceback
return jsonify({'status': 'error', 'val': traceback.format_exc()})
def init(): # Funtion to initialize a connection to a PLC and retrive data from it
seqs, tags = {}, {}
ipOK, slotOK = False, False
ipRegex = re.compile(r'''
(\d{1,3}\.){3}\d{1,3}$ # IPv4
| ([0-9abcdef]{4}:){7}[0-9abcdef]{4}$ # IPv6
| ^cancel$ # Cancel the operation
''', re.VERBOSE|re.I)
slotRegex = re.compile(r'''
\d+$ # Any digit
| ^cancel$ # Cancel the operation
''', re.VERBOSE|re.I)
while ipOK == False:
ip = re.match(ipRegex, input("PLC IP Address: ").strip()) # Request the PLC IP address and check it is the correct format
if ip: # IP address format OK
if ip.group().lower() == 'cancel':
print('Operation cancelled\n')
return None, seqs, tags
else:
ipOK = True # IP Address OK, allow user to enter slot
else: # IP address format not OK
print('Format of IP address was incorrect')
while slotOK == False:
slot = re.match(slotRegex, input("Rack slot: ").strip()) # Request the rack slot number
if slot: # Slot format OK
if slot.group().lower() == 'cancel':
print('Operation cancelled\n')
return None, seqs, tags
else:
slotOK = True
else: # Slot format not OK
print('Format of slot was incorrect')
try:
print(f"Initializing connection to {ip.group()}/{str(slot.group())}")
plc = LogixDriver(f"{ip.group()}/{str(slot.group())}", init_tags=True, init_program_tags=True) # Set up the LogixDriver for the stated PLC. This is returned to be used within other functions
if plc.open(): # Open the connection to the PLC and read data from it
print("Connection to PLC established")
plcInfo = plc.info # Write the PLC info to a variable
del plcInfo['tasks'] # Remove tasks from plcInfo as it is not required
del plcInfo['modules'] # Remove modules from plcInfo as it is not required
programs = plcInfo.pop('programs') # Pop the 'programs' dictionary item into a variable
for prog in programs.keys(): # Go through the programs and search for a sequence regex (Sxx where x are digits)
mo1 = re.search(r'^S\d\d', prog)
if mo1 != None:
mo2 = re.search(r'\d\d', mo1.group()) # Search for the digits in the matched object and use them as keys in the sequences dictionary
seqs.setdefault(mo2.group(), prog) # Assign the key (sequence number) and value (program name) to the sequences dictionary
seqs = keySortDict(seqs) # Sort the sequence dictionary based on sequence number (keys)
plcInfo.update({'revision':f"Major : {str(plcInfo['revision']['major'])} / Minor : {str(plcInfo['revision']['minor'])}"})
table = Table(box=box.ROUNDED) # Create a table
table.add_column('PLC Information', justify='left') # Add column
table.add_column('Sequences', justify='left') # Add column
textInfo = '\n'.join(f"{k.capitalize().replace('_', ' ').ljust(15)} | {v}" for k, v in plcInfo.items()) # Combine the PLC information into one string
textSeq = '\n'.join(f"{k} - {v}" for k, v in seqs.items()) # Combine the PLC sequences into one string
table.add_row(textInfo, textSeq) # Add row
print(table)
for k, v in seqs.items(): # Loop for each sequence selected by the user
maxStep = plc.read(f"zzSeq[{k}].MaxStepNo").value
tags.setdefault(k,
[f"zzSeq[{k}].MaxStepNo",
f"Program:{v}.zzSteptimeLast[1]{{{maxStep}}}",
f"Program:{v}.zzSteptimeLong[1]{{{maxStep}}}",
f"Program:{v}.zzSteptimeShort[1]{{{maxStep}}}",
f"Program:{v}.zzStepRefTime[xxTypexx,1]{{{maxStep}}}"]) # Add the sequence tags to the dictionary of tags
print(f"Initialized step tags for sequence {k}: {v}, max step = {str(maxStep)}")
plc.close()
else:
print('Failed to establish connection to PLC')
except Exception:
plc.close()
traceback.print_exc()
return plc, seqs, tags # Return the LogixDriver and a key sorted dictionary of sequence programs in the connected PLC
class allenbradley_logix(driver):
'''
This driver supports services specific to ControlLogix, CompactLogix, and Micro800 PLCs.
The driver is based on the library pycomm3: https://github.com/ottowayi/pycomm3.
Parameters:
ip : String : ip address of the PLC
'''
def __init__(self, name: str, pipe: Optional[Pipe] = None):
"""
:param name: (optional) Name for the driver
:param pipe: (optional) Pipe used to communicate with the driver thread. See gateway.py
"""
# Inherit
driver.__init__(self, name, pipe)
self.ip = '192.168.0.1'
def connect(self) -> bool:
""" Connect driver.
: returns: True if connection stablished False if not
"""
# Create connection
try:
self._connection = LogixDriver(self.ip)
self._connection.open()
except Exception as e:
self.sendDebugInfo(f"Connection with {self.ip} cannot be stablished.")
return False
# Check connection status.
if self._connection.connected:
return True
else:
self.sendDebugInfo(f"Driver not connected.")
return False
def disconnect(self):
""" Disconnect driver.
"""
if self._connection:
self._connection.close()
def addVariables(self, variables: dict):
""" Add variables to the driver. Correctly added variables will be added to internal dictionary 'variables'.
Any error adding a variable should be communicated to the server using sendDebugInfo() method.
: param variables: Variables to add in a dict following the setup format. (See documentation)
"""
for var_id in list(variables.keys()):
var_data = dict(variables[var_id])
try:
var_data['value'] = None
self.variables[var_id] = var_data
except Exception as e:
self.sendDebugInfo(f'SETUP: {e} \"{var_id}\"')
def readVariables(self, variables: list) -> list:
""" Read given variable values. In case that the read is not possible or generates an error BAD quality should be returned.
: param variables: List of variable ids to be read.
: returns: list of tupples including (var_id, var_value, VariableQuality)
"""
res = []
try:
values = self._connection.read(*variables)
if not isinstance(values, list):
values = [values]
for (tag, value, _, error) in values:
if error:
res.append((tag, None, VariableQuality.BAD))
else:
res.append((tag, value, VariableQuality.GOOD))
except Exception as e:
self.sendDebugInfo(f'exception reading variable values: {e}')
return res
def writeVariables(self, variables: list) -> list:
""" Write given variable values. In case that the write is not possible or generates an error BAD quality should be returned.
: param variables: List of tupples with variable ids and the values to be written (var_id, var_value).
: returns: list of tupples including (var_id, var_value, VariableQuality)
"""
res = []
try:
values = self._connection.write(*variables)
if not isinstance(values, list):
values = [values]
for (tag, value, _, error) in values:
if error:
res.append((tag, value, VariableQuality.BAD))
else:
res.append((tag, value, VariableQuality.GOOD))
except Exception as e:
self.sendDebugInfo(f'exception writing variable values: {e}')
return res