Device Family: Cyclone® V E, Cyclone® V GT, Cyclone® V GX, Cyclone® V SE, Cyclone® V ST, Cyclone® V SX
Area: EMIF, Intellectual Property
IP Product: DDR3 SDRAM Controller MegaCore supporting UniPHY
No, you do not need to add user assignments for the hard memory controller dedicated ground pins. You only need to connect these pins to ground on the board.