Using fieldbus technology in the control strategy > DeltaV fieldbus function blocks in the control strategy

Fieldbus function blocks must be assigned to devices

If a module contains any <unassigned> fieldbus function blocks, the LAS is unable to generate the schedule for the entire module even if the module contains properly linked and assigned function blocks.

You are notified of any <unassigned> modules during a download of the fieldbus device. In Control Studio, right-click the function block, and then click Assign to fieldbus Device.