Parameter data exchange
An intelligent IO-Link sensor/actuator can support parameterization by ISDU (Indexed Service Data Unit). The PLC must explicitly query or, when marked as such, send these acyclic service data.
 | Access ISDU TwinCAT supports access via ADS and via the CoE directory. |
The respective parameter is addressed via the so-called ISDU index. The following ranges are available:
Name | Index range |
|---|---|
System | 0x00..0x0F |
Identification | 0x10..0x1F |
Diagnostic | 0x20..0x2F |
Communication | 0x30..0x3F |
Preferred Index | 0x40..0xFE |
Extended Index | 0x0100..0x3FFF |
| the range 0x4000..0xFFFF is reserved |
The use of the implementation of these ranges is the responsibility of the sensor/actuator vendor. For clarification you see only some possible indices with designation listed here. Refer to the corresponding chapter in the info system Object description and parameterization.
Direct parameters
The indices 0x0000 and 0x0001 are special parameters that each IO-Link device possesses. An IO-Link master requires the information from Direct Parameter 1 to establish IO-Link communication with the device.
Index | Subindex | Name | Flag | Type | Definition |
|---|---|---|---|---|---|
Direct Parameter1 | |||||
0x0000 | 0x01 | Reserved | ro | UINT8 | Reserved |
0x0000 | 0x02 | Master Cycle Time | ro | UINT8 | Master cycle time |
0x0000 | 0x03 | Min Cycle Time | ro | UINT8 | Minimum cycle time |
0x0000 | 0x04 | M-Sequence Capability | ro | UINT8 | M sequence |
0x0000 | 0x05 | IO-Link Version ID | ro | UINT8 | IO-Link Revisions-ID |
0x0000 | 0x06 | Process Data Input Length | ro | UINT8 | Process data input length |
0x0000 | 0x07 | Process Data Output length | ro | UINT8 | Process data output length |
0x0000 | 0x08 | Vendor ID 1 | ro | UINT8 | Vendor ID 1 |
0x0000 | 0x09 | Vendor ID 2 | ro | UINT8 | Vendor ID 2 |
0x0000 | 0xA | Device ID1 | ro | UINT8 | Device ID 1 |
0x0000 | 0xB | Device ID 2 | ro | UINT8 | Device ID 2 |
0x0000 | 0xC | Device ID3 | ro | UINT8 | Device ID 3 |
0x0000 | 0xD | Reserved | ro | UINT8 | Reserved |
0x0000 | 0xE | Reserved | ro | UINT8 | Reserved |
0x0000 | 0xF | Reserved | ro | UINT8 | Reserved |
Direct Parameter 2 | |||||
0x0001 | 0x01 | Device Specific Parameter 1 | rw | UINT8 | Device-specific |
0x0001 | 0x02 | Device Specific Parameter 2 | rw | UINT8 | Device-specific |
0x0001 | 0x03 | Device Specific Parameter 3 | rw | UINT8 | Device-specific |
0x0001 | 0x04 | Device Specific Parameter 4 | rw | UINT8 | Device-specific |
0x0001 | 0x05 | Device Specific Parameter 5 | rw | UINT8 | Device-specific |
0x0001 | 0x06 | Device Specific Parameter 6 | rw | UINT8 | Device-specific |
0x0001 | 0x07 | Device Specific Parameter 7 | rw | UINT8 | Device-specific |
0x0001 | 0x08 | Device Specific Parameter 8 | rw | UINT8 | Device-specific |
0x0001 | 0x09 | Device Specific Parameter 9 | rw | UINT8 | Device-specific |
0x0001 | 0xA | Device Specific Parameter 10 | rw | UINT8 | Device-specific |
0x0001 | 0xB | Device Specific Parameter 11 | rw | UINT8 | Device-specific |
0x0001 | 0xC | Device Specific Parameter 12 | rw | UINT8 | Device-specific |
0x0001 | 0xD | Device Specific Parameter 13 | rw | UINT8 | Device-specific |
0x0001 | 0xE | Device Specific Parameter 14 | rw | UINT8 | Device-specific |
0x0001 | 0xF | Device Specific Parameter 15 | rw | UINT8 | Device-specific |
0x0001 | 0x10 | Device Specific Parameter 16 | rw | UINT8 | Device-specific |
Specified parameters
The standard IO-Link parameters are also listed here.
Index | Subindex | Name | Flag | Type | Definition |
|---|---|---|---|---|---|
Device Access Locks | |||||
0x000C | 0x01 | Parameter (Write ) Access Lock | rw s | BOOL | Locks the write access |
0x000C | 0x02 | Data Storage Lock | rw s | BOOL | Locks the Data Storage access |
0x000C | 0x03 | Local Parametrization Lock | rw s | BOOL | Locks the local parameter access |
0x000C | 0x04 | Local Userinterface Lock | rw s | BOOL | Locks the local user interface |
Detection parameters | |||||
0x0010 | 0x00 | Vendor Name | ro | STRING | Vendor name |
0x0011 | 0x00 | Vendor Text | ro | STRING | Vendor text |
0x0012 | 0x00 | Product Name | ro | STRING | Product name |
0x0013 | 0x00 | Product ID | ro | STRING | Product ID |
0x0014 | 0x00 | Product Text | ro | STRING | Product text |
0x0015 | 0x00 | Serial Number | ro | STRING | Serial number |
0x0016 | 0x00 | Hardware version | ro | STRING | Hardware version |
0x0017 | 0x00 | FirmwareVersion | ro | STRING | Firmware version |
0x0018 | 0x00 | ApplicationSpecificTag | rw | STRING | Application specific text |
0x0019 | 0x00 | Function Tag | rw | STRING | Function text |
Device Status and Detailed Device Status
The parameters 0x0024 Device Status and 0x0025 Detailed Device Description are optional parameters for standard IO-Link devices. However, if an IO-Link device supports profiles, these parameters are mandatory.
Index | Subindex | Name | Flag | Type | Definition |
|---|---|---|---|---|---|
0x0024 | 0x00 | Device Status | ro | Uint8 | Device status |
Detailed Device Status | |||||
0x0025 | 0x01 | Detailed Device Status | ro s | OctetString | Event of an IO-Link device |
0x0025 | 0x02 | Detailed Device Status | ro s | OctetString | Event of an IO-Link device |
0x0025 | 0x03 | Detailed Device Status | ro s | OctetString | Event of an IO-Link device |
0x0025 | 0x04 | Detailed Device Status | ro s | OctetString | Event of an IO-Link device |
If an IO-Link device does not support the parameter 0x0025, the event history can also be read from the CoE parameter 0x10F3 using the FB_EcCoeSdoRead function block.
