Attributes of Modular Device Object

Anybus Support Embedded
#1

Attribute #3: Number of instances:

Accordingly to the “Network Guide for Profibus” and the “Software Design Guide” the value of this attribute corresponds to the number of physically connected modules. Which means per connected module a instance and the “Coupler”-Module which is always there.

For example there exists two types of modules:

  • Module Speed with Module ID 0x0000 0002

  • Module Ref Speed with Module ID 0x0000 0004

and the coupler with ( Do not exist in the GSD-File)

  • Module Coupler with ID 0x0000 0001

The following modules are connected:

  • Module Speed with Module ID 0x0000 0002

  • Module Ref Speed with Module ID 0x0000 0004

  • Module Speed with Module ID 0x0000 0002

Which value should be set ? Is the coupler counted as well ? What about instance 0x0h which corresponds to the Object ?

Attribute #4: Highest instance no. :

The “Network Guide for Profibus” says: Highest connected module
and the “Software Design Guide”: Instance number of the last occupied slot, i.e. the highest instance number currently used.

Similar questions as for Attribute #3, is the coupler counted as well ? What about instance 0x0h which corresponds to the Object ?

Which value should be set for the given example ?

Thanks !

#4

Attribute #3: Number of instances:
There are three modules that are connected plus the coupler, which is counted and is instance 1. This means the response is 4. However, this answer assumed there were no empty slots.
Attribute #4: Highest instance no: For the example this would also be 4. It’s the three modules plus the coupler.