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The Xentara Siemens S7 Driver v1.1.2
User Manual
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The Xentara Siemens S7 Driver v1.1.2
User Manual
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A data item maps a single variable in the target device to the Xentara model tree as a skill data point. The data item must refer to an address in the target S7 PLC and has a defined data type. In addition, it must be configured as a member of a command to be read and written.
Data items that refer to a memory area located in data blocks of the target PLC must be defined as children of the corresponding data block objects.
S7 data items have the following attributes:
| key | The data item’s primary key. |
| name | The data item’s name. The name is the last component of the primary key. |
| UUID | The unique UUID of the data item. |
| type | The data item’s element type. For S7 data items, this is always “S7 data item”. |
| category | The data item’s category. For S7 data items, this is always “data point”. |
| value | The value of the data item. |
| quality | The quality of the current value. |
| error | The last read error. |
| writeError | The last write error. This attribute is available only if the data item is writable. |
| changeTime | The last time the value was changed. |
| writeTime | The last time the value was written. This attribute is available only if the data item is writable. |
The Xentara S7 driver supports the following S7 data types:
| Data Type | Description |
|---|---|
| Bool | Boolean value (true or false) |
| Byte | unsigned 8-bit integer |
| Word | unsigned 16-bit integer |
| DWord | unsigned 32-bit integer |
| SInt | signed 8-bit integer |
| USInt | unsigned 8-bit integer |
| Int | signed 16-bit integer |
| UInt | unsigned 16-bit integer |
| DInt | signed 32-bit integer |
| UDInt | signed 32-bit integer |
| Real | 32-bit IEEE 754 floating point value |
| LReal | 64-bit IEEE 754 floating point value |
| String | A string of 8-Bit characters |