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Honored Contributor
Honored Contributorsimultaneous access to ddrII memory by nios and vhdl entity
Hi all, I am using Arria II device.Basicly,what i need to do is to transfer large amounts of bulk data,which is stored in DDR2 memory using Ethernet to PC.The problem is that vhdl-based entity is ...
Altera_ForumHonored Contributor
Honored ContributorHi,
The easiest way is probably to create an Avalon master for your VHDL entity, either enclosing it entirely or just providing an interface from the Avalon bus to your entity outside of SOPC builder. If you then connect both your master and the NIOS processor to the memory controller in SOPC builder the Avalon bus will take care of arbitration between the two. However, it's arbitration is very fair which might not be what you want - for example, you might want your VHDL entity to have priority access over the NIOS CPU. Have a look at the multi-port front end design on the Altera website for some arbitration ideas (part of the UDX4 reference design). Mark.
