_OPCServer (OPC client)
Through the server datapoint, the properties of a server are set and the server's status information is made available. The values are displayed in the OPC server panel (see Panel OPC server).
For each server that is to be started via its config entry, a data point of type _OPCServer must be present before the OPC client is started. The name must be composed according to the following convention:
_ + symbolic server name"server1"
Symbolic name: server1
Name of the internal data point of type _OPCServer: _server1
| DP element | Type | Description |
|---|---|---|
| BandWidth | uint | The value of this field depends on the server. It should give the load on the server as a percentage. Values over 100% signal that too many items with too high an update rate are being requested. Servers that don't support an exact load specification should return the value 0xFFFFFFFF. This value cannot be set by the user. |
| BuildNumber | uint | Build number of the server software. This value cannot be set by the user. |
| Connected | bit | Is set by the driver: (TRUE), if there is a connection to the corresponding server. It is reset (FALSE), when the connection is interrupted. This value cannot be set by the user. |
| CurrentTimeBias | uint [ms] | This value cannot be set by the user. Difference between the time stamp of the server status and the current system time. |
| DeleteServer | bit | When a value of 1 is written to this element, the associated server is stopped. The server is not started again until the driver is restarted. |
| GetItemIds | bit | Writing a value triggers an update of the information in ItemIds. |
| GroupCount | uint | Total number of groups (public and private) contained in the server. This value also includes groups created by other clients in the server. This value cannot be set by the user. |
| InvalidMapping | bit | If this value is TRUE, the invalid bit is set by the driver when the OPC quality information is BAD or UNCERTAIN. This setting can be combined with all possible settings of QualInfoFilter.QualInfo and QualInfoFilter.QualInfoDetail. |
| ItemIds | dyn. text array | The server's address space is shown in this field, if the server supports this function and address browsing is enabled via the config file. This value cannot be set by the user. |
| LastUpdateTime | time | Time of the last update by the server in local time. This value cannot be set by the user. |
| MajorVersion | uint | Major version of the server software. This value cannot be set by the user. |
| MinorVersion | uint | Minor version of the server software. This value cannot be set by the user. |
|
QualInfoFiltet. QualiInfo |
uint | The value of this data point specifies which part of the OPC quality information is mapped on to the user bits. |
|
QualInfoFilter. QualInfoDetail |
uint | This value specifies the user bits on to which the part of the quality information selected under QualInfoFilter.QualInfo is mapped (see Table below) |
| ReconnectTimer | uint [s] | After an interrupt of the client-server connection, the client attempts to restore the connection to the server. This value gives the length in seconds of the interval after which the client tries a reconnect. CAUTION: This value should not be made too low, as otherwise a reconnect is tried before the server has executed the shutdown. (~20 seconds) |
| ServerGA | bit | A change of value in this field triggers a general query on the server, in which all items in all groups of the respective server are queried. Whether this query is answered from the server cache or directly from the periphery depends on the value in _OPCGroup.DataSourceDevice, and can be set per group. See section on "_OPCGroup (OPC Client)". |
| ServerState | uint |
The status supplied by the server as a number according to the OPC specification. This value cannot be set by the user. EXAMPLE: ServerState = 1 ServerStateText = OPC_STATUS_RUNNING |
| ServerStateText | string |
If an OPC Standard ServerState appears in ServerState, this value is supplied in text form here. This value cannot be set by the user. EXAMPLE: ServerState = 1 ServerStateText = OPC_STATUS_RUNNING |
| StartTime | time | This value cannot be set by the user. It specifies the time (local time) at which the server was started. |
| StateTimer | int [s] | This value sets the seconds interval at which the server status is queried. Since the status query (together with a callback mechanism) is used for monitoring the connection, this value should not be made too high. (1 - 30 seconds). For 0, the server status is not queried. |
| VendorInfo | string | Manufacturer-specific information on the server. This value cannot be set by the user. |
| BrowseInfo.GetBranch | dyn_String | This DPE triggers the browsing of a hierarchical level in the server. The first element is currently ignored. The second element must contain the ItemId of the node for which the child nodes shall be read. |
| BrowseInfo.BranchNames | dyn_string | Contains the names of all child nodes starting from the parent node. |
| BrowseInfo.BranchQuery | dyn_string | Mirrored GetBranch command. |
| BrowseInfo.HierarchySeparator | char | Separator for the hierarchy levels. |
| HierarchicalBrowsing | bit | Obsolete. |
| ContainedItemCnt | uint | Contains the number of all items added to the server's groups. |
| TimeoutError | int |
This element contains information of timeout errors that occurred during server accesses. Possible values: 0...no error 1...Timeout error during read 2...Timeout error during write 3...Timeout error during refresh 4...Timeout error during readback |
| TimeoutItems | dyn_string | All elements that raise a timeout error during a read/write access of the OPC server are added to this list. |
The following table shows the mapping for the different combinations of values of QualInfoFilter.QualInfo and QualInfoFilter.QualInfoDetail. The unused user bits are not interpreted by the driver in the command direction, and not set in the alert direction.
| QualInfoFilter. QualInfo | QualInfoFilter. QualInfoDetail | Meaning |
|---|---|---|
| 0 | Don't care | No quality mapping, no user bit set |
| 1 | 0 | The low byte of the OPC quality information is mapped onto the 8 user bits |
| 8 | Quality and substatus of the OPC quality information are mapped onto bits 1 to 6. | |
| 9 | Quality and substatus of the OPC quality information are mapped onto bits 2 to 7. | |
| 10 | Quality and substatus of the OPC quality information are mapped onto bits 3 to 8. | |
| 16 | Map limit information onto user bits, beginning at bit 1 | |
| 17 | Map limit information onto user bits, beginning at bit 2 | |
| 18 | Map limit information onto user bits, beginning at bit 3 | |
| 19 | Map limit information onto user bits, beginning at bit 4 | |
| 20 | Map limit information onto user bits, beginning at bit 5 | |
| 21 | Map limit information onto user bits, beginning at bit 6 | |
| 22 | Map limit information onto user bits, beginning at bit 7 | |
| 32 | Map sub state onto user bits, beginning at bit 1 | |
| 33 | Map sub state onto user bits, beginning at bit 2 | |
| 34 | Map sub state onto user bits, beginning at bit 3 | |
| 35 | Map sub state onto user bits, beginning at bit 4 | |
| 36 | Map sub state onto user bits, beginning at bit 5 | |
| 2 | Don't care | The high byte of the OPC quality information (server-specific information) is mapped onto the 8 user bits |
