How to deal with I&M data?
Overview
Identification & Maintenance (I&M) is an integral part of each Profinet Device implementation. It provides standarized information about a device and its parts. The I&M Information is accessible through Profinet Record Objects and is always bound to a submodule belonging to the item to be described. An item means here the Profinet Device itself or a part of this device e.g. a plugable module for modular devices. Submodules can provide own I&M objects or share the I&M objects of other submodules. The I&M objects can be grouped into three kinds of information as described as follows.
I&M0 is a read only information which describes the associated item. The following fields are defined:
| Field | Description | Usage Hints |
|---|---|---|
| Vendor ID | The PNO Vendor ID of the associated item. E.g the vendor of the device or the vendor of a pluggable module/submodule. | This is the Vendor ID of the manufacturer of the item and not the Vendor ID of the Profinet Protocol Vendor. Do not use the Hilscher Vendor ID. |
| Order ID | The order id of the associated item. | Order ID as defined by the manufacturer of the item. Must be equal to any order id markings on the item itself. |
| Serial Number | The serial number of the associated item. | Must be an unique serial number associated with the item. Must be equal to any serial number markings on the item itself |
| Hardware Revision | The revision of the hardware of the item. | Must be equal to any hardware revision markings on the item itself. |
| Software Revision | The software revision of the item | This is the software version of the whole item including the Profinet Protocol Implementation and the Application. This version is managed by the manufacturer of the item. It must be changed whenever a part of the software within the item (including the Profinet Protocol implementation if it is part of the item) changes. This is not the version number of the Profinet Protocol Implementation. Do not use the Hilscher Version of the Profinet Protocol Implementation. |
| Revision Counter | Counts the changes of I&M1 to I&M4 objects | |
| Profile ID | The Profile of the item if applicable. | |
| Profile Specific Type | ||
| Supported I&M objects | Bitmask defining which I&M objects are supported by this item. |
The I&M1 to I&M4 objects provide a non-volatile storage for Profinet Engineering related information. This information is typically generated by the engineering software and stored within the objects at engineering time. The information must be stored by the device in non-volatile memory. The objects must be stored physically within the associated item. That means in particular, if a plugable module is removed from one backplane and plugged into another backplane, it must deliver the same I&M1 to I&M4 information as stored before.
Finally, the I&M5 record provides information about the Profinet Protocol Implementation itself. It is quite similar to I&M0 but describes the Prodifet Protocol Implementation instead. Thus it is handled by the Profinet Protocol Implementation itself.
Structure and access paths of I&M objects
The following picture illustrates the structural organization of I&M Records within a device and the access paths:
According I&M a submodule can be characterized as follows:
- The submodule is a representative for the module. That means that the submodule provides the I&M information of the superordinate module.
- The submodule is a representative for the device. In that case the submodule provides the I&M information of the superordinate device. Exactly one submodule of the device must have this property. Typicall the DAP submodule is choosen for that purpose.
When reading the I&M objects of a submodule the following order is used to deliver the requested data:
- If the submodule provides an own I&M0 object, the I&M read access will deliver the submodule's I&M objects
- If the submodule has no own I&M0 object and the superordinate module has a module representative, the module representative's I&M objects will be delivered.
- If the submodule has no own I&M0 object and the superordinate module has no representativ the device representatives's I&M objects will be delivered.
In contrast to that, writing I&M1 to I&M4 objects is only possible on the submodules associated with the I&M objects itself.
Usage of I&M with Hilscher Profinet Protocol
The Profinet Device Protocol Implementation of Hilscher supports two modes of operation with I&M. For simple applications the Profinet Protocol Implementation provides I&M0 to I&M5 objects within the DAP submodule. In that case the I&M is fully handled by the Profinet Protocol Implementation without any interaction with the Application. If a more complex I&M structure is required, the Profinet Protocol Implementation can forward I&M accesses to the Application. In that case all I&M objects must be handled by the application. The desired mode of operation is configured using the Set Configuration Service.
If the Profinet Protocol Implementation is handling the I&M internally, the following parameters will be used within the I&M0 object:
| Field | Source of value |
|---|---|
| Vendor ID | Vendor ID in Set Configuration Service or Configuration Database. Can be overriden by tag list if Configuration Database is used. |
| Order ID | Order ID in Set Configuration Service or Configuration Database. |
| Serial Number | Defaults to the serial number from Security Memory / Flashlabel. This is the serial number of the Hilscher communication module if applicable. It shall be changed to the serial number of the manufacturers device using the Set OEM Parameters service. |
| Hardware Revision | Hardware revision in Set Configuration Service. If a Configuration Database is used the hardware revision from Security Memory / Flashlabel is used. This is the hardware revision of the Hilscher communication module if applicable. |
| Software Revision | Software revision in Set Configuration Service. If a Configuration Database is used the Profinet Protocol Implementations software revision will be used. |
| Revision Counter | Internally stored an incremented on each change of I&M1 to I&M4. |
| Profile ID | Defaults to '0x00' (Manufacturer specific) Can be changed to desired value using Set OEM Parameters service. |
| Profile Specific Type | Defaults to '0x05' (Generic Device) Can be changed to desired value using Set OEM Parameters service. |
| Supported I&M objects | Defaults to I&M0 to I&M5. Can be changed to desired value using Set OEM Parameters service. |