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Honored Contributor
Honored ContributorDDR SDRA IP local address
I try to use DDR SDRAM IP controller. I need it for 1 Gbyte DDR memory. after setting the block and the controller sign that we have 1 Gbyet memory we only get 26 address line, and we need 27 ad...
Altera_ForumHonored Contributor
Honored ContributorThe number of address bits are determined by this formula:
log2 ([SDRAM address span * 8] / [SDRAM local data width]) For a given memory device the address span is fixed so if you wanted more or less address bits you need either wider or more narrow memory. Assuming you are mastering this memory with a 64-bit data path then you would just wire the word addresses from the memory master to the SDRAM controller. You may have the last 27th address bit floating but that just means you are not using up the entire addressable memory of your master.
