ID:84041 <name> mode must have output_register in <name> device family

CAUSE: You select the specific mode of the altmult_add megafunction and choose no register at output; however, you cannot use the specified mode with out output_register. This error usually occurs when you instantiate a megafunction directly in a text file rather than using the MegaWizard Plug-In Manager .

ACTION: To avoid receiving this message in the future, change unregistered to clock0/clock1/clock2/clock3. Intel recommends using the MegaWizard Plug-In Manager.