Application Data Instances (ADIs)
ADIs can be accessed acyclically from the network by means of Record Data read/write services. If addressed through a given API and Index range, the module translates the service into standard object requests towards the Application Data Object. If the host application responds with an error to such a request, that error will be translated to PROFINET standard.
The following parameters affect the addressing of ADIs on PROFINET:
Application Process Instance (API) | API 0 (zero) provides access to data in the Application Data Object, i.e. the ADIs. Acyclic requests towards other APIs will be forwarded to the PROFINET IO Object (F6h) by means of the ‘Get_Record’ and ‘Set_Record’-commands. The remainder of this section assumes API 0 (zero). |
Slot & subslot | The Slot and subslot values have no impact on the actual addressing of ADIs, except that the actual Slot and subslot need to be populated with a module/submodule. This is always true for the DAP (Device Access Point), which occupies Slot #0/subslot #1. Other Slot/subslot values can also be used provided that the implementation populates it with a module/submodule. |
Index | There is a 1:1 correlation between ADI and index as long as the index number is less than - or equal to - 7FFFh. Index 0 (zero) is not associated with an ADI and cannot be used. |
API | Slot | Subslot | Index | ADI | Comments |
|---|---|---|---|---|---|
0 | 0 | 1 | 0000h | - | (not associated with ADIs) |
0001h | 1 | Device Access Point (DAP) | |||
0002h | 2 | ||||
... | ... | ||||
7FFFh | 32767 | ||||
8000h...FFFFh | - | (not associated with ADIs) | |||
X (>0) | Y | 0000h | |||
0001h | 1 | Conditional; X and Y must be populated | |||
0002h | 2 | ||||
... | ... | ||||
7FFFh | 32767 | ||||
8000h...FFFFh | - | (not associated with ADIs) | |||
>0 | - | - | - | - |
See also...