OpenOPC ======= OpenOPC for Python 3.x is a descendent of http://openopc.sourceforge.net with modifications for Python 3 and distutils. About OpenOPC ------------------- OpenOPC for Python is a free, open source OPC (OLE for Process Control) toolkit designed for use with the popular Python programming language. Software Developers ------------------- If you elected to install the OpenOPC Development library during the installation process, then you'll need to also download and install the following packages in order to develop your own Python programs which use the OpenOPC library: 1. Python 3.4+ http://www.python.org/download/ 2. Python for Windows Extensions (pywin32) http://sourceforge.net/projects/pywin32/ 3. Pyro4 https://github.com/irmen/Pyro4 Of course, Python is necessary on all platforms. However the other packages may be optional depending on your configuration: 1. Win32 platform, using the OpenOPC Gateway Service Pywin32: optional Pyro4: required 2. Win32 platform, talking to OPC Servers directly using COM/DCOM Pywin32: required Pyro4: optional 3. Non-Windows platform (use of Gateway Service is mandatory) Pywin32: not applicable Pyro4: required In order to get the most from the OpenOPC package, Windows developers are encouraged to install both Pywin32 and Pyro. Using Pyro to talk to the Gateway Service provides a quick and easy method for bypassing the DCOM security nightmares which are all too common when using OPC. Documentation ------------- A PDF manual for OpenOPC is included in this installation inside the "doc" folder. Users are encouraged to also look at the OpenOPC web site for additional usage examples that may not be contained in the manual. EXAMPLE: Minimal working program import OpenOPC opc = OpenOPC.client() opc.connect('Matrikon.OPC.Simulation') print(opc['Square Waves.Real8']) opc.close() OpenOPC Command-line Client --------------------------- OpenOPC includes the only publically available command-line OPC client. Unlike graphical clients, it can be easily used in scripts or batch files. And because of its piping capability (i.e. chaining commands together), it is far more powerful than other OPC clients. 1. Get a listing of the available OPC servers on your computer by going to the command prompt and entering: opc -q 2. Set your prefered OPC server as the default by setting the system wide enviornment variable OPC_SERVER. (On Windows you can do this by going to Control Panel > System > Advanced > Environment Variables) OPC_SERVER=Matrikon.OPC.Simulation 3. Display OPC server information via the Win32 COM connection: opc -i 4. Test to see if the OpenOPC Gateway Service is functioning by entering: opc -m open -i 5. Test some of the other commands available using the OPC Command Line Client. To get started, try entering the opc command without any arguments in order to see the help page: opc To read an item from your OPC server, just include the item name as one of your arguments. For example, if you're using Matrikon's Simulation server you could do: opc Random.Int4 To read items from a specific OPC server you have installed, include the -s switch followed by the OPC server name. For example: opc -s Matrikon.OPC.Simulation Random.Int4 To list available items: C:\> opc -f Random.*Int* Random.Int1 Random.Int2 Random.Int4 Random.UInt1 Random.UInt2 Random.UInt4 To read values of items every 60 seconds, logging the results to a file until stopped by Ctrl-C...: C:\> opc Random.Int4 Random.Real8 -L 60 >data.log Command usage summary: C:\> opc OpenOPC Command Line Client 1.1.6 Copyright (c) 2007-2008 Barry Barnreiter (barry_b@users.sourceforge.net) Usage: opc [OPTIONS] [ACTION] [ITEM|PATH...] Actions: -r, --read Read ITEM values (default action) -w, --write Write values to ITEMs (use ITEM=VALUE) -p, --properties View properties of ITEMs -l, --list List items at specified PATHs (tree browser) -f, --flat List all ITEM names (flat browser) -i, --info Display OPC server information -q, --servers Query list of available OPC servers -S, --sessions List sessions in OpenOPC Gateway Service Options: -m MODE, --mode=MODE Protocol MODE (dcom, open) (default: OPC_MODE) -C CLASS,--class=CLASS OPC Automation CLASS (default: OPC_CLASS) -n NAME, --name=NAME Set OPC Client NAME (default: OPC_CLIENT) -h HOST, --host=HOST DCOM OPC HOST (default: OPC_HOST) -s SERV, --server=SERVER DCOM OPC SERVER (default: OPC_SERVER) -H HOST, --gate-host=HOST OpenOPC Gateway HOST (default: OPC_GATE_HOST) -P PORT, --gate-port=PORT OpenOPC Gateway PORT (default: OPC_GATE_PORT) -F FUNC, --function=FUNC Read FUNCTION to use (sync, async) -c SRC, --source=SOURCE Set data SOURCE for reads (cache, device, hybrid) -g SIZE, --size=SIZE Group tags into SIZE items per transaction -z MSEC, --pause=MSEC Sleep MSEC milliseconds between transactions -u MSEC, --update=MSEC Set update rate for group to MSEC milliseconds -t MSEC, --timeout=MSEC Set read timeout to MSEC mulliseconds -o FMT, --output=FORMAT Output FORMAT (table, values, pairs, csv, html) -L SEC, --repeat=SEC Loop ACTION every SEC seconds until stopped -y ID, --id=ID,... Retrieve only specific Property IDs -a STR, --append=STR,... Append STRINGS to each input item name -x N --rotate=N Rotate output orientation in groups of N values -v, --verbose Verbose mode showing all OPC function calls -e, --errors Include descriptive error message strings -R, --recursive List items recursively when browsing tree -, --pipe Pipe item/value list from standard input If you experience any unexpected errors, please check the FAQ on http://openopc.sourceforge.net for additional help. If after reading through the FAQ you still require additional help, then the author of this package would be happy to assist you via e-mail. Please see the project website for current contact information. Technical Support ----------------- If you have any questions, bug reports, or suggestions for improvements please feel free to contact the author at: barry_b@users.sourceforge.net While I cannot always guarantee a quick response, I eventually respond to all e-mails and will do my best to slove any issues which are discovered. Thanks for using OpenOPC for Python! Credits ------- Copyright (c) 2008-2012 by Barry Barnreiter (barry_b@users.sourceforge.net) Copyright (c) 2014 by Anton D. Kachalov (mouse@yandex.ru) Copyright (c) 2017 by Michal Kwiatkowski (michal@trivas.pl) http://openopc.sourceforge.net/ https://github.com/ya-mouse/openopc https://github.com/sightmachine/OpenOPC