/pyLSV2

A pure Python3 implementation of the LSV2 protocol

Primary LanguagePythonMIT LicenseMIT

pyLSV2

PyPI pyversions PyPI version fury.io Documentation Status

This library is an attempt to implement the LSV2 communication protocol used by certain CNC controls. It's main goal is to transfer file between the application and the control as well as collect information about said files. Over time more and more functions where added which support gathering information from the control.

Most of this library is based on the work of tfischer73 and his Eclipse plugin found at his GitHub page. Since there is no free documentation beside the plugin, some parts are based purely on reverse engineering and might therefore be not correct.

As long as no encrypted communication is necessary, no additional librarys are necessary.

Please consider the dangers of using this library on a production machine! This library is by no means complete and could damage the control or cause injuries! Everything beyond simple file manipulation is blocked by a lockout parameter. Use at your own risk!

License

MIT License

Copyright (c) 2020 - 2021 drunsinn

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

News and Releases

check the github release page for information on the latest updates

Contributors

In chronological order:

  • tfischer73
  • drunsinn
  • WouterElfrink
  • kekec14
  • Michal Navrátil

Compatibility

Since there are a lot of different software versions and machine configurations out there it is hard to say if this library is compatible with all of them. Most testing has been done on programming stations but also with real hardware. Here is a list of versions that have been tested:

Programming Stations

Control Software
TNC640 340595 08 SP1
TNC640 340595 10 SP2
TNC640 340595 11 SP1
iTNC530 606425 04 SP20
CNCpilot640 1230521 03 SP1

Machines

Control Software
TNC640 340595 08 SP1
iTNC530 340480 14 SP4
iTNC530 606420 02 SP14
iTNC530 606420 02 SP3

If you have tested it on one of your machines with a different software version, please let us know!

Take a look at protocol.rst for a more in depth explanation on the detials of LSV2.

Usage

See lsv2_demo.py for a demonstration of some of the functions.

Notice that the definitionns of constant values will be moved from pyLSV2.LSV2 to pyLSV2 directly!

Basic example

 import pyLSV2
 con = pyLSV2.LSV2('192.168.56.101')
 con.connect()
 print(con.get_versions())
 con.disconnect()

Reading Information from the control

 import logging
 import pyLSV2
 
 logging.basicConfig(level=logging.DEBUG)
 con = pyLSV2.LSV2('192.168.56.101', safe_mode=False)
 con.connect()
 print(con.get_program_status_text(con.get_program_status()))
 print(con.get_execution_status_text(con.get_execution_status()))
 con.disconnect()

File transfer

 import logging
 import pyLSV2
 
 logging.basicConfig(level=logging.DEBUG)
 con = pyLSV2.LSV2('192.168.56.101', safe_mode=True)
 con.connect()

 con.send_file(local_path='./test.H', remote_path='TNC:/',
               override_file=True, binary_mode=True)

 con.recive_file(local_path='./', remote_path='TNC:/nc_prog/$mdi.h',
                 override_file=True, binary_mode=True)

 con.disconnect()

Accessing PLC data

To read values from the PLC memory you need to know the memory area/type and the memory address. There are two ways to read these values.

Reading via memory address

The following command reads 15 marker (bits) starting at address

 con.read_plc_memory(address=32, mem_type=pyLSV2.PLC_MEM_TYPE_MARKER, count=15)

See lsv2_demo.py for more examples.

The available memory aread and their python data type

Memory Type Python Type
PLC_MEM_TYPE_MARKER bool
PLC_MEM_TYPE_INPUT bool
PLC_MEM_TYPE_OUTPUT bool
PLC_MEM_TYPE_COUNTER bool
PLC_MEM_TYPE_TIMER bool
PLC_MEM_TYPE_BYTE integer
PLC_MEM_TYPE_WORD integer
PLC_MEM_TYPE_DWORD integer
PLC_MEM_TYPE_STRING str
PLC_MEM_TYPE_INPUT_WORD integer
PLC_MEM_TYPE_OUTPUT_WORD integer

Reading via Data Path

The following command reads values from the control not via a memory address but via supplying a data access path. This will only work on iTNC controls! The advantage is that it also allows you to access tables like the tool table without reading the complete file.

 con.read_data_path('/PLC/memory/K/1')
 con.read_data_path('/TABLE/TOOL/T/1/DOC')

See lsv2_demo.py for more examples.

SSH Tunnel

Newer controls allow the use of ssh to encrypt the communication via LSV2. See scripts/ssh_tunnel_demo.py for an example on how to use the python library sshtunnel to achieve a secure connection.

Testing

To run the test you either need a machine or a programming station. The controls has to be on and the PLC program has to be running. You can add the IP-Address and timeout as a parameter

 pytest --address=192.168.56.103 --timeout=5

Resources

https://www.inventcom.net/support/heidenhain/read-tnc-plc-data

https://de.industryarena.com/heidenhain/forum