7.18 UA_ReadList
| FB-Name | UA_ReadList | |||
| This Function Block is used to read values of multiple nodes using a list of node handles. | ||||
| VAR_INPUT | ||||
| B | Execute | BOOL | On rising edge node information will be read. | |
| B | ConnectionHdl | DWORD | Connection handle. | |
| B | NodeHdlCount | UINT | Number of valid elements in the array to read. | |
| B | NodeHdls | ARRAY OF DWORD | Array of Node Handles. Length is vendor-specific (MAX_ELEMENTS_NODELIST). See Constants of Array Lengths | |
| B | NodeAddInfos | ARRAY OF UANodeAdditionalInfo | See UANodeAdditionalInfo. Array of UANodeAdditionalInfo. Specifies the attribute and IndexRange. Length is vendor-specific (MAX_ELEMENTS_NODELIST). See Constants of Array Lengths This parameter is optional. If not existing the UAAI_Value (13) will be taken from internal implementation. | |
| B | Timeout | TIME | Time to response. | |
| VAR_OUTPUT | ||||
| B | Done | BOOL | FB has completed its task. | |
| B | Busy | BOOL | The FB is not finished and new output values are to be expected | |
| B | Error | BOOL | Signals that an error has occurred within the FB. Set to TRUE if either ErrorID or any of the NodeErrorIDs indicates an error. | |
| B | ErrorID | DWORD | Error code for the OPC UA service call. | |
| B | NodeErrorIDs | ARRAY OF DWORD | Array of DWORD. Contains an error code for each valid element of the Variables array. Length is vendor-specific (MAX_ELEMENTS_NODELIST). See Constants of Array Lengths | |
| B | TimeStamps | ARRAY OF Vendor specific | Shall be DT or LDT. The recommendation for new implementation is to use LDT. Contains a TimeStamp for each valid element of the Variables array. Length is vendor-specific (MAX_ELEMENTS_NODELIST). Constants of Array Lengths Constants of Array Lengths This parameter is optional. If not existing the internal client implementation shall not ask for any timestamp from server side. | |
| VAR_IN_OUT | ||||
| B | Variables | ARRAY OF Vendor specific | Vendor specific. Length is vendor-specific (MAX_ELEMENTS_NODELIST). See Constants of Array Lengths | |
Notes: Vendors can handle “Variables” in a vendor specific way. Independent of the vendor specific solution the mapping of the controller data type and OPC UA data type shall be handled in the function block. VAR_IN_OUT: “Variables” as would provide best type save solution for users: The client firmware is able to map the UA memory layout to the controller layout. The firmware client can receive the type definition from the OPC UA Server. A “Variable” could be the name of the variable so the internal firmware can get address, length, data type of variable. | ||||
| UA_ReadList | ||||||
| BOOL | Execute | Done | BOOL | |||
| DWORD | ConnectionHdl | Busy | BOOL | |||
| UINT | NodeHdlCount | Error | BOOL | |||
| ARRAY OF DWORD | NodeHdls | ErrorID | DWORD | |||
| ARRAY OF STRUCT | NodeAddInfos | NodeErrorIDs | ARRAY OF DWORD | |||
| TIME | Timeout | TimeStamps | ARRAY OF Vendor specific | |||
| ARRAY OF Vendor specific | Variables | Variables | ARRAY OF Vendor specific | |||