Device Family: Arria® V GX, Stratix® III, Stratix® IV E, Stratix® IV GT, Stratix® IV GX, Stratix® V E, Stratix® V GS, Stratix® V GT, Stratix® V GX

Type: Answers

Area: EMIF, Intellectual Property

IP Product: RLDRAM II Memory Controller

What is the value of the constantBurstBehavior property in my DDR3 SDRAM Controller with UniPHY?


The Avalon Memory-Mapped Interface has a property constantBurstBehavior which declares how the master/slave should handle the address and burstcount signals. When constantBurstBehavior is set to true, address and burstcount must be held stable throughout a burst. When constantBurstBehavior is set to false, address and burstcount are sampled on the first transaction of a burst so it does not matter if address and burstcount change during all subequent transactions of a burst.

The UniPHY based controllers have constantBurstBehavior set to false and only require that the address (avl_addr) and burstcount (avl_size) remain stable during the first transaction of a burst.