Process Data Info and Configuration¶
Description¶
Process data information and configuration offers various possibilities related to process data:
Selection of a process dataset specified by the device
Information about the structure of the input and output data
Information about the last valid value for input and output data
As a diagnosis function, monitoring of the updates of certain process values is available. If these are not updated in the specified time, the device sends corresponding diagnosis messages.
Invalid Process Data¶
Input data (from the device to the master) is only marked as invalid if the device has the Failure device status.
ISDU¶
| Name | Index | Subindex | Access | Length | Data Type | Data Storage | Default |
|---|---|---|---|---|---|---|---|
| Process Data Profile Selection | 0x0051 (81) | 0 | R/W | 1 byte | UINT8(ENUM) | Yes | 0x01 |
| Process Data Input Descriptor | 0x000E (14) | 0 | R | 21 bytes | UINT8[] | n/a | – |
| Last Valid Process Data Inputs | 0x0028 (40) | 0 | R | 12 bytes | – | n/a | – |
PD Profile Selection¶
There is only one PD Profile
PD Description¶
This parameter is used to specify the structure of the currently selected process data profile for input and output data. The individual process data variables are described.
The total list is accessible via subindex 0, a single entry is possible using a specific subindex. Subindex 1 corresponds to the least significant (or the element most recently transferred in the process data stream). When reading out the entire list, this element is transferred first.
The length of the list is dependent on which process data profile is selected. A single element has a length of 3 bytes.
| Byte number | Contents | Values |
|---|---|---|
| Byte 1 | Data type | 0: OctetStringT 1: Set of BoolT 2: UIntegerT 4: Float32T 5…255: reserved |
| Byte 2 | TypeLength | 0…255 bits |
| Byte 3 | Bit offset | 0…255 bits |
Last Valid Process Data¶
This parameter indicates the most recently valid input or output data of the device. The first transferred byte in the process data (MSB) is transferred first. This is an exact representation. Access occurs via subindex 0.
Events¶
PD Update Timeout¶
With special process data values, the device automatically checks whether the values are updated in the time period specified by the device. If an update timeout is triggered as a result, this is output via the following diagnosis messages:
| Event Code | Event Type | Event – Description – Remedy | Device Status |
|---|---|---|---|
| 0x1851 (6225) | Notification | Process Data Update Timeout – for information purposes only. A PDinput has been delayed over an extended period of time. | 0 – Device is operating properly. |
| 0x1852 (6226) | Warning | Multiple Process Data Update Timeout – for information purposes only. A PDinput has been delayed over an extended period of time. | 0 – Device is operating properly. |
PD Profile Selection after Change of Variant¶
If the variant of the device is changed, the currently set profile is retained.
In the case that the corresponding PD profile is not valid for this variant, the default profile for the corresponding variant is selected.
| Event Code | Event Type | Event – Description – Remedy | Device Status |
|---|---|---|---|
| 0x1850 (6224) | Notification | Process data profile selection cannot be used – default value is used. | 0 – Device is operating properly. |
Variant Dependence¶
There is no variant dependency in PD-Profiles. All variants use the same PD-profile.
PD Invalid¶
PD Inputs Invalid:
Input data (device-to-master) is marked as invalid if the device status (see section Device status and detailed device status) of the device is Failure. In all other states, replacement values for the data are output for which the content cannot be output correctly.