>For certain addressing patterns, the refresh can be eliminated
>alltogether, when the addressing sequence is such that all (used)
>memory cells are naturally being read, and thus refreshed, within the
>required time.

That happens in a couple of common cases...

Running video refresh out of DRAM
Running DSP code
Running memory tests

I once worked on a memory board that worked better (at least as
measured by memory diagnostics) when the refresh was clipleaded out.
(We had a bug in the arbiter.)

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