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There is another way to determine software reset completion, except waiting for tRPH.
tRPH is counted from when CS# is brought high at the end of the software reset command. You have to wait at least tRPH for software reset completion, before next flash access (i.e., bring CS# low again). There is no maximum time limit for the waiting (i.e., you can wait as long as you want, as far as longer than tRPH). So there is only Min value of tRPH, no Maximum value of tRPH.
In another word, waiting for tRPH is enough for software reset to complete.
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