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Supported device types and versions
Communication line configuration
Communication station configuration
I/O tag configuration
Setting The setting of the right strategy for data reading
DCOM configuration for connecting to connect to remote OPC remote server
Errors and problems
Literature
Changes and modifications
Document revisions
Supported device types and versions
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The protocol supports a implements client side of communication with OPC (OLE for Process Control) HDA (Historical Data Access) servers according to specifications OPC HDA ver. 1.20.
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- OPC Host: It is required only for "Remote" access, i.e. it is defined only for OPC server type "Remote" (string max. 50 characters). OPC HDA Server must be installed on a computer. You can se enter the names according to UNC (Universal Naming Convention) (e.g. "\\server" or "server"), DNS domain names (e.g. "domain.com", "example.company.com") or IP address ("196.54.23.113").
- Backup Host: It is required only for "Remote" access. It is a backup OPC host. If it is defined, D2000 KOM tries to establish a communication alternately with OPC Host and Backup Host after a failure of communication.
- OPC Server: A name (ProgID) of OPC server (string max. 50 characters).
- Server Type: "InProc", "Local" or "Remote".
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You may configure the following station parameters:
Table 1
Key word| Keyword | Full name | Meaning | Unit | Default value |
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| Full Debug | It turns the debug records on. It significantly increases the number of information about |
the | communication. We recommend |
you to activate | activating it only when detecting problems and debugging |
of | communication. | YES/NO | NO |
| Reconnect/Reinitialisation Delay | Delay after the following failed operations:- creating of items - GetItemHandles,
- reconnection to OPC HDA Server after it failed, was stopped or
|
disconnected via - a network disconnect,
- creating of items after reconnection to OPC HDA Server.
| sec | 5 |
| Include Bounds | It sets the |
parameter | "Bounds" parameter (the reading of the threshold limits of interval even if they are beyond the interval) in synchronous/asynchronous reading of "raw" values. | YES/NO | NO |
| Async Mode | It sets an asynchronous mode of activity when data reading. See the chapter |
Setting the Integer | An integer value of "ERROR" status for conversion to the quaternary input Qi. | 0,1,2,3 | 3 |
| QOFF Value |
Integer | An integer value of "OFF" status for conversion to the quaternary input Qi. | 0,1,2,3 | 2 |
| QON Value |
Integer | An integer value of "ON" status for conversion to the quaternary input Qi. | 0,1,2,3 | 1 |
| QTRANS Value |
Integer | An integer value of "TRANS" status for conversion to the quaternary input Qi. | 0,1,2,3 | 0 |
| Map ExtraData as flag | Mapping of "Extra Data" OPC HDA flag of quality |
Extra Data | to the attributes of I/O tag value. | None, FA, FB, FC, FD, FE, FF, FG, FH, FI, FJ, FK, FL, FM, FN, FO, FP | None |
| Map Interpolated as flag | Mapping of "Interpolated" OPC HDA flag of quality |
Interpolated | to the attributes of I/O tag value. |
| Map Raw as flag | Mapping of "Raw" OPC HDA flag of quality |
Raw | to the attributes of I/O tag value. |
| Map Calculated as flag | Mapping of "Calculated" OPC HDA flag of quality |
Calculated | to the attributes of I/O tag value. |
| Map NoBound as flag | Mapping of "No Bound" OPC HDA flag of quality |
No Bound | to the attributes of I/O tag value. |
| Map NoData as flag | Mapping of "No Data" OPC HDA flag of quality |
No Data | to the attributes of I/O tag value. |
| Map DataLost as flag | Mapping of "Data Lost" OPC HDA flag of quality |
Data Lost | to the attributes of I/O tag value. |
| Map Conversion as flag | Mapping of "Conversion" OPC HDA flag of quality |
Conversion | to the attributes of I/O tag value. |
| Map Partial as flag | Mapping of "Partial" OPC HDA flag of quality |
Partial | to the attributes of I/O tag value. |
| Map NonSpecific as flag | Mapping of "Non Specific" OPC DA flag of quality |
Non Specific | to the attributes of I/O tag value. |
| Map LocalOverride as flag | Mapping of "LocalOverride" OPC DA flag of quality |
LocalOverride | to the attributes of I/O tag value. |
| Map ConfigError as flag | Mapping of "Config Error" OPC DA flag of quality |
Config Error | to the attributes of I/O tag value. |
| Map NotConnected as flag | Mapping of "Not Connected" OPC DA flag of quality |
Not Connected | to the attributes of I/O tag value. |
| Map DeviceFailure as flag | Mapping of "Device Failure" OPC DA flag of quality |
Device Failure | to the attributes of I/O tag value. |
| OPCQFSF | Map SensorFailure as flag | Mapping of "Sensor Failure" OPC DA flag of quality |
Sensor Failure | to the attributes of I/O tag value. |
| Map LastKnown as flag | Mapping of "Last Known" OPC DA flag of quality |
Last Known | to the attributes of I/O tag value. |
| Map CommFailure as flag | Mapping of "Comm Failure" OPC DA flag of quality |
Comm Failure | to the attributes of I/O tag value. |
| Map OutOfService as flag | Mapping of "Out Of Service" OPC DA flag of quality |
Out Of Service | to the attributes of I/O tag value. |
| Map WaitingForInitData as flag | Mapping of "Waiting For Initial Data" OPC DA flag of quality |
Waiting For Initial Data | to the attributes of I/O tag value. |
| Map LastUsable as flag | Mapping of |
OPC | "Last Usable" OPC DA flag of quality |
Last Usable | to the attributes of I/O tag value. |
| Map SensorCal as flag | Mapping of |
OPC | "Sensor Cal" OPC DA flag of quality |
Sensor Cal | to the attributes of I/O tag value. |
| Map EGUExceeded as flag | Mapping of "EGU Exceeded" OPC DA flag of quality |
EGU Exceeded | to the attributes of I/O tag value. |
| Map SubNormal as flag | Mapping of "Sub Normal" OPC DA flag of quality |
Sub Normal | to the attributes of I/O tag value. |
I/O tag configuration
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I/O tag types: Ai, Ci, Di, Qi, TiA, TiR, TxtI.
The address of the I/O tag requires to set "OPC Item ID" (string max. 200 characters).
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- The selection between "Raw" and "Processed" type of value which is read.
- If you choose "Processed", then set also "Aggregate".
- The option "Async Advise" to permit the asynchronous continuous data acquisition.
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The setting of the right strategy for data reading
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OPC Historical Data Access is a specification that enables to read the historical data - either "raw" or "processed". Data may be read by the synchronous or asynchronous callings. The asynchronous interface enables also "advise" of required data, i.e. a periodical (see the parameter "Update Interval") sending of the current values from OPC HDA Server by the the asynchronous call-back in a client - KOM process. The only required interface, according to the specification of OPC HDA, is "SyncRead" for the reading of "raw" data synchronously.
In D2000 KOM Process, the protocol OPC HDA protocol is implemented in the a way that enables as effective as possible the reading of archive data as effectively as possible, including the updating of the last values, so that it avoids to combine combining "OPC Historical Access" protocol with "OPC Data Access" one. The GETOLDVAL tell command GETOLDVAL enables to call trigger the reading of historical data in any time interval. The obtained data are saved to D2000 Archiv if the primary archive value was used for archiving of the particular I/O tag.
The current data may be acquired in using two waysstrategies:
- Minimalist:
It uses only the synchronous interface "SyncRead". According to the setting of of station time parameters, the functions "ReadRaw" and "ReadProcessed" functions are called periodically. The required interval of values starts from the time of the last valid value up to the current time. If several values have been received in a given interval, the last value with the latest time stamp timestamp is considered to be a current value. The other values are sent as "old" values to the server and are stored to in the D2000 Archiv. - Advise:
It uses the functions of asynchronous interface "AsyncRead", "AdviseRaw", and "AdviseProcessed". OPC HDA Server sends the last valid data of "raw" or "processed" items in the period which is defined in the parameter "Update Interval". If any no new value is not in the defined interval, OPC HDA Server returns the flag of quality "No Data" quality flag.
The parameter "Async Mode" parameter enables to set setting a fully asynchronous mode, which uses only the "AsyncRead" interface. However, the asynchronous mode has some limitations that , which is why we do not recommend it in these situations:
- When reading of "raw" data asynchronously, a repeated reading of data that were not in one could not be returned by a single call is not supported (the flag OPC_S_MOREDATA flag is returned).
- In asynchronous mode, there is not resolved the right timing of finishing the transaction of tell command GETOLDVALthe GETOLDVAL command is not implemented. It causes an ineffective saving of received values by D2000 Archiv.
The protocol OPC Historical Data Access protocol does not support the data writing (the interfaces "SyncUpdate" and "ReadUpdate"). Also, the interfaces "SyncAnnotations", "AsyncAnnotations", "Browser" and "Playback" interfaces are not supported.
DCOM configuration for connecting to ...
remote OPC
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server
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Remote browsing/local registration of OPC Server
Since the version 7.01.020 rel. 055 and higher, the D2000 KOM Process supports the acquisition of GUID OPC Servers' GUIDs from ProgID which is placed on remote desktops computers via DCOM interface with the help of OPCENUM utility OPCENUM (remote browsing). If the OPCENUM utility/windows service OPCENUM has been installed on a remote OPC server and the level of access rights enables a remote browsing, the local registration of the OPC server is not necessary on the side of the client side. The OPCENUM utility OPCENUM is a part of package the "OPC Core Components Redistributable" package. You can find it on http://www.opcfoundation.org/, or in or as a part of OPC Server installation.
The registration of the OPC Server is not necessary on the side of the OPC client side (D2000 KOM). However, if you decide to register it, you can use one of these two ways:
- Some of the OPC Servers are supplied with a setup program to support the connection of OPC clients of "third partsparties" to the remote OPC Server. These programs are named for example "OPC Server Connect". After their installing, OPC Server (its ProgID) occurs appears in the list of OPC Servers on the clients PCclient computer. D2000 OPC Client will use this information only for getting of CLSID from ProgID (see the communication line configuration). The registered OPC Server, however, cannot be operated on the client-side.
- Manual registration of OPC Server on the client side. Follow these steps:
- Copy OPC Server (.exe file + necessary .dll files) into the auxiliary directory on the client PC.
- Start a command line in this directory.
- Register OPC Server. If OPC Server is named e.g. "OPCSERVER.EXE" on the disk, then write the command:
"OPCSERVER.EXE /regserver"
and press ENTER. - Delete the auxiliary directory.
Always read the instructions for installation OPC Server and check your steps with those stated in the manual.
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The setting of access rights
The connection to the remote OPC Server is subject to the access right control of Windows. From For this reason, the same user (together with the password) must be created on both the computer. On the OPC client side, the user must be logged on. On the OPC Server, the user must have some certain access rights therefore follow these instructions:
- Start the program "DCOMCNFG" in the command line on a computer with OPC Server. Check, if DCOM is enabled - the option "Enable Distributed COM on this computer" option.
- Find OPC Server in the list and open the "Properties" dialog window. Open tab the "Security" tab.
- Switch "Launch Permissions" to "Customize" and click on the button "Edit..." button.
- Check the particular user in the list or add him to it.
- Do the same for "Access Permissions".
Wrong setting of the access rights will probably cause an error (see the chapter "COM/OPC error dump" chapter):
ERROR: ServerProgID caused COM/OPC error 80070005H on CoCreateInstanceEx(CLSCTX_REMOTE_SERVER), Error string : Access is denied.
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You can avoid this problem, if you add a group "Everyone" to "Launch Permissions" and "Access Permissions". To ensure that the OPC Server will be started under the particular user account (and no under "SYSTEM account"), open the "Identity" tab and fill the data for "This user". In this case, you cannot consider OPC Server to be a safesafely configured.
OPC Client (D2000 KOM) is not allowed to be started as "Windows service" with parameters "/X1" or "/X2", because then it does not work under the logged-on user but under "SYSTEM account". An authentication Authentication of the access rights by the OPC Server will fail. Use a start parameter "/X4".
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For the user of WindowsXP (or higher) with SP2, we recommend to change changing the parameter "Network access: Let Everyone permissions apply to anonymous users" to "Enabled" in the settings "Local Security Policy/Security Options".
| Info |
|---|
| title | Note about SIMATIC NET and possibly other OPC servers |
|---|
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If the OPC server is configured to run under "The interactive user" on the last tab Identity of the "Properties" dialog window, it may cause the OPC server to be available only when a user is logged on the computer. We recommend to change changing this setting to "The launching user", "This user", resp. "The system account". |
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The error messages, mentioned below, may occur during the start, or during communication. It is recommended to activate the monitoring of communication in the configuration of the line for easier identification of problemproblems. You can choose it from these levels:
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When you set "Monitor & Disk" or "Disk", the file "line_name.LOG" occurs in the subdirectory "\TRACETrace" in subdirectory of the application directory on the computer with the running communication process. This file contains all the debug and error messages.
| Error: | Unconvertible value for Item: 'ItemID', I/O tag: 'IOTagName'! |
| Description: | The received value cannot be converted to a suitable value type of I/O tag in D2000. Customize the value type of I/O tag. |
| Error: | ShutDown OPC HDA Server : 'ServerProgID' ! |
| Description: | OPC server has been stopped correctly in spite of it |
has the | having active clients. |
| Error: | OPC HDA Server 'ServerProgID' is unavailable ! |
| Description: | Remote DCOM OPC Server is unavailable. D2000 KOM (a client) will retry to connect to the server. Check the PC on which OPC Server is installed (whether it is running and properly connected to a local network). |
| Error: | Async reading raw data failed, Item: 'ItemID' |
| Description: | Error when calling "ReadRaw" of the interface "AsyncRead". Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | Sync reading raw data failed, Item: 'ItemID' |
| Description: | Error when calling "ReadRaw" of the interface "SyncRead". Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | Async reading processed data failed, Item: 'ItemID' |
| Description: | Error when calling "ReadProcessed" of the interface "ReadAsync". Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | Sync reading of processed data failed, Item: 'ItemID' |
| Description: | Error when calling "ReadProcessed" of the interface "ReadSync". Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | SetCallBack - FAILED, Server: 'OPCServerProgID'. |
| Description: | Error when registering the asynchronous call-back procedure. Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | OPCConnectToServer - FAILED, Host: 'ServerName', Server: 'OPCServerProgID'! |
| Description: | Failure of connection to OPC Server. Check COM/OPC error dump to gain |
a | detailed information. |
| Error: | AsyncAdviseRaw - FAILED, I/O tag: 'IOTagName', ItemID: 'ItemID', Station: 'StationName' |
| Description: | Error when calling "AdviseRaw" of the interface "ReadAsync". Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | AsyncAdviseProcessed - FAILED, I/O tag: 'IOTagName', ItemID: 'ItemID', Aggregate='Aggregate', Station: 'StationName' |
| Description: | Error when calling "AdviseProcessed" of the interface "ReadAsync". Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | GetItemHandle - FAILED, I/O tag: 'IOTagName', ItemID: 'ItemID', Station: 'StationName' ! |
| Description: | Error when calling "GetItemHandles" of the interface "Server". The registration of the required item failed. Since the validation of the item name was successful (the call "ValidateItemIDs"), check a log file of the OPC Server. Check COM/OPC error dump to |
gain a | obtain detailed information. |
| Error: | ValidateItem - FAILED, I/O tag: 'IOTagName', ItemID: 'ItemID', Station: 'StationName' ! |
| Description: | Failure of the calling "ValidateItemIDs" of the interface "Server". There is probably an unknown ItemID. Check COM/OPC error dump to |
gain a | obtain detailed information. |
COM/OPC error dump
The error messages mentioned in the chapter "Errors and problems" are generated in a higher level of OPC client. The most Most of the mentioned errors will be described on COM/OPC level. The format of these error messages is as follows:
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These error messages are important for an analyzes analysis of the problem. If any problems occur, they will be required by a the technical support of the Ipesoft company.
Literature
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