what the mean of Assembly Instance in RSLogix5000

Hi, folks, how are you?

On our production line, we use AB RSLogix5000 as main PLC to control fanuc robots via ControlNet. So I checked the properties of controlnet module.
Could you tell me what the mean of Assembly Instance?

Thanks a lot.

Assembly instances are a code and data structure to allow communications to a device over CIP (Common Industrial Protocol). Each device generally supports 3 concurrent ones, an Input instance, an Output instance, and a Configuration instance. Some devices may support different interfaces for any or all of the three depending on the instance code.

As an example, maybe a drive can report back just its speed under one input instance, or 40 different values under another input instance.

For a thorough description, see the ODVA CIP Protocols Paper and look at Assembly Objects.