MVME328S-1工控模塊系統(tǒng)備件
OPC通過定義一個通用的高性能接口消除了這一要求,該接口允許這項工作只完成一次,然后可以被HMI、SCADA、控制和定制應(yīng)用程序輕松重用。原則上,只要DriveWindow實現(xiàn)了數(shù)據(jù)訪問標(biāo)準(zhǔn)1.0A的強(qiáng)制性自定義界面和IOPCBrowseServerAddressSpace,它就可以作為任何OPC服務(wù)器的用戶界面。但是,DriveWindow包含許多與驅(qū)動器相關(guān)的功能,這些功能要求OPC服務(wù)器為DriveOPC。DriveOPC包含在DriveWindow的安裝中。安裝DriveWindow時,也會安裝DriveOPC。OPC服務(wù)器有兩個版本:?進(jìn)程內(nèi)服務(wù)器(SMP.DLL)。它只能在本地使用。?本地服務(wù)器(SMP.EXE)。它在遠(yuǎn)端使用,但也可以在本地使用。如果客戶端程序在本地使用OPC服務(wù)器,則可以在連接到OPC服務(wù)器時選擇要使用的版本。然而,DriveWindow與許多其他客戶端程序一樣,將選擇委托給操作系統(tǒng),操作系統(tǒng)選擇進(jìn)程內(nèi)服務(wù)器(如果可用)。如果沒有,則選擇本地服務(wù)器。如果需要,可以通過寄存器更改使進(jìn)程內(nèi)服務(wù)器停止使用。但是,根據(jù)您的操作系統(tǒng)及其配置方式,也可以“遠(yuǎn)程”使用本地服務(wù)器(EXE)版本。通常,遠(yuǎn)程連接到\\localhost或127.0.0.1實際上連接到同一臺PC中的本地服務(wù)器。當(dāng)使用DriveOPC進(jìn)程內(nèi)服務(wù)器(DLL)時,在同一臺電腦中同時運(yùn)行的每個客戶端程序都會獲得自己的服務(wù)器實例。DriveOPC中有一個內(nèi)部鎖,只允許一個實例使用通信庫。例如,如果多個DriveWindow同時運(yùn)行并連接到本地進(jìn)程內(nèi)服務(wù)器,則只有第一個可以看到驅(qū)動器,其他人什么都看不到。自DriveOPC 2.02版(包含在DriveWindow 2.01中)以來,如果庫的另一個實例已在運(yùn)行,則通信庫會顯示一個消息框。但是,請注意,如果DriveOPC配置為遠(yuǎn)程使用,則不會顯示該消息。注意,本地服務(wù)器(EXE)也使用通信庫。因此,它也是庫中使用內(nèi)部鎖的“客戶”之一。高級信息驅(qū)動窗口2 10-5在本地或遠(yuǎn)程(如果配置正確)使用本地服務(wù)器(EXE)時,多個客戶端可以同時連接和使用服務(wù)器。但是,DriveWindow始終檢查其他DriveWindow實例是否試圖使用同一服務(wù)器。如果是這種情況,DriveWindow拒絕連接,并通知用戶同時使用,首先是一條詳細(xì)的錯誤消息,然后是一個更容易理解的解釋:另請參閱:什么是OPC服務(wù)器離線OPC服務(wù)器2.1遠(yuǎn)程使用信息由于DCOM涉及安全風(fēng)險,我們不建議遠(yuǎn)程使用DriveOPC。DriveOPC沒有用戶界面,基于COM技術(shù),因此也可以通過DCOM遠(yuǎn)程使用。DriveWindow也可以連接到遠(yuǎn)程OPC服務(wù)器。但是,需要在本地安裝相同的OPC服務(wù)器,因為DriveWindow在本地獲取可用服務(wù)器的列表。
OPC eliminates this requirement by defining a common, high performance interface that permits this work to be done once, and then easily reused by HMI, SCADA, Control and custom applications. In principle, DriveWindow is able to act as a user interface for any OPC Server as long as it implements the obligatory custom interfaces and IOPCBrowseServerAddressSpace of the Data Access Standard 1.0A. However, DriveWindow contains many drive dependent features, which require that the OPC Server is DriveOPC. DriveOPC is included in the installation of DriveWindow. When you install DriveWindow, you get also DriveOPC installed. There are two versions of an OPC Server: ? In-process server (SMP.DLL). It can be used only locally. ? Local server (SMP.EXE). It is used at the remote end, but can also be used locally. If a client program uses the OPC Server locally, it can select, which version to use, when connecting to the OPC Server. DriveWindow, however, like many other client programs, delegate the selection to the operating system, which selects the in-process server, if it is available. If not, local server is selected. The in-process server can be taken out of use by a register change, if needed. However, depending on your operating system and how it is configured, it may also be possible to use the local server (EXE) version “remotely”. Typically, connecting remotely to \\localhost or 127.0.0.1, actually connects to the local server in the same PC. When using DriveOPC in-process server (DLL), each client program running simultaneously in the same PC gets its own instance of the server. There is an internal lock within DriveOPC, which allows only one instance to use the communication library. If, for example, more than one DriveWindow are running simultaneously and connect to the local in-process server, only the first one is able to see the drives, others see nothing. Since DriveOPC version 2.02 (included in DriveWindow 2.01), the communication library shows a message box, if another instance of the library is already running. Note, however, that the message is not shown in case DriveOPC is configured to be used remotely. Note that also the local server (EXE) uses also the communication library. So it is also one of the “clients” competing about the use of the internal lock in the library.Advanced Information DriveWindow 2 10-5 When using the local server (EXE) either locally or remotely (if properly configured), several clients can connect and use the server simultaneously. DriveWindow, however, always checks, if other DriveWindow instances are trying to use the same server. If that is the case, DriveWindow refuses to connect, and informs the user about the simultaneous use, first with a detailed error message and immediately after that with a more understandable explanation: See Also: What is OPC Server OfflineOPC Information about OPC Server 2.1 Remote Use Because of security risks involved in DCOM, we do not recommend using DriveOPC remotely. DriveOPC does not have a user interface and is based on COM technology, so it can be used also remotely through DCOM. DriveWindow has the ability to connect to a remote OPC Server, too. It is required, however, that the same OPC Server is also installed locally, because DriveWindow gets the list of available servers locally.