如何形容python 的 openopc库

OpenOPC for Python is a free, open source OPC (OLE for Process Control) toolkit designed for use with the popular Python programming language. The unique features that set it apart from the many commercially available OPC toolkits include...

Easy to use

Because the OpenOPC library implements a minimal number of Python functions which may be chained together in a variety of ways, the library is simple to learn and easy to remember. In its simplest form, you can read and write OPC items as easily as any variable in your Python program... print opc['Square Waves.Int4'] opc['Square Waves.Real8'] = 100.0 Cross platform support

OpenOPC works with both Windows and non-Windows platforms. It has been tested with Windows, Linux, and Mac OS X. Functional programming style

OpenOPC allows OPC calls to be chained together in an elegant, functional programming style. For example, you can read the values of all items matching a wildcard pattern using a single line of Python code! opc.read(opc.list('Square Waves.*')) Designed for dynamic languages

Most OPC toolkits today are designed for use with static system languages (such as C++ or C#), providing a close mapping to the underlying Win32 COM methods. OpenOPC discards this cumbersome model and instead attempts to take advantage of the dynamic language features provided by Python.

OpenOPC is also one of the very few OPC-DA toolkits available for any dynamic language, and future support is planned for Ruby. EXAMPLE: Minimal working program

import OpenOPC

opc = OpenOPC.client()

opc.connect('Matrikon.OPC.Simulation')

print opc['Square Waves.Real8']

opc.close()

This project utilizes the de facto OPC-DA (Win32 COM-based) industrial automation standard. If you are looking for an OPC XML-DA library for Python, then please visit the PyOPC project.

OpenOPC Gateway Service

The Gateway Service is an optional Windows service which handles all the Win32 COM/DCOM calls used by the OpenOPC library module. This offers the following potential advantages:

Avoidance of DCOM security headaches and firewall issues when running the OPC client and OPC server on different nodes. The ability to write OPC client applications that can run on non-Windows platforms such as Linux, Unix, and Mac OS X. Installing the service

C:\OpenOPC\bin>OpenOPCService.exe -install

Installing service OpenOpcService

Service installed

Starting the service

C:\OpenOPC\bin>net start zzzOpenOpcService

Stopping the service

C:\OpenOPC\bin>net stop zzzOpenOpcService

NOTE: If you want to use the OpenOPC Gateway service from another machine as a client and are using OpenOPC 1.2 then you must set the environment variable in windows and restart the gateway service:

OPC_GATE_HOST=x.x.x.x