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楼主 |
发表于 2014-11-25 09:40:43
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回复 6# qw342333
Thank you very much!
In my understanding, read leveling includes several steps such as MPR reading and normal reading. For MPR reading, the memory controller reads "01010101" patterns from the MPR of the SDRAM, to aliagn the read DQS to the center of the valid DQ window. Then the memory controller writes some fixed pattern to the SDRAM and reads them back from the same location, to adjust the DQS phase more precisely. During the calibration, it needs to find the left bound and the right bound just as you have said, to define the valid data window.
This is my understanding now, maybe not correct as well... |
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