Description
Yes. A x16 DDR SDRAM device usually uses 2 DQS pins where each DQS pins drives 8 DQ pins. For Cyclone, you need to instantiate 2 sets of x8 DQ/DQS group for the x16 DDR SDRAM operation.
Similarly if you are using a x32 DDR SDRAM device where 4 DQS are used to drive 8 DQ pins each, you need to instantiate 4 sets of x8 DQ/DQS group.
Altera's definition of x16 or x32 mode is 1 DQS pin driving 16 or 32 DQ pins respectively. Cyclone devices do not support x16 and x32 mode in this definition.