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Altera_Forum's avatar
Altera_Forum
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16 years ago

DDR 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_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Yes that's correct, that is how the local address is mapped to the multiplexed address that is sent to the SDRAM device.

You mentioned that accessing address 0 and 1 mapped to the same memory cells, were you performing burst accesses on the local side? If so are you aware of SDRAM burst wrapping? Basically if you perform a burst access that crosses a burst boundary then the address wraps around which might be why you are seeing this overlapping issue.