AnsweredAssumed Answered

How to distinguish between DDR calibration and power saving feature?

Question asked by Takayuki Ishii on May 28, 2017
Latest reply on Sep 6, 2017 by Zhang Lin


In imx6 Reference manual(IMX6DQRM.pdf), it say that
Power saving features should be disabled before the calibration
process begin.


How to distinguish between DDR3 calibration and power saving feature?


I think, in normal operation, it must enable auto ZQ calibration,
Upon hardware or software self-refresh request assertion,
Disable ZQ calibration first, and enable auto power saving.

Is it correct?


In our customer, when both calibration and automatic power saving are
enable, their LCD output will stop and system will hung-up.

Which mechanism do it happen?


Best regards,