AnsweredAssumed Answered

adv7842 ddr-sdram

Question asked by mbu on Oct 1, 2012
Latest reply on Oct 11, 2012 by mbu



We have a new design with an adv7842 and an external DDR ram, MT46V16M16P-6T from Micron Technology, Inc.

Setting up the adv7842 to receive CVBS on Ain10.


When I enable the Frame time-based correction (TBC ) the signal out from the adv7842 becomes extremely noisy.


I have followed the recommended settings from the documentation (in particular 12.5.1 from  UG-214).

The same settings works fine on the EVAL-board.


By cooling down the adv7842 and the Ram during configuration (reset of memory controller sdp_io 0x60[0]) it sometimes

shows an improved performance. This last until warmed up again.


From this we assume that the problem is timing-related.


Could you provide more information about the configuration of the memory controller ?


Registers such as:

sdp_io 0x74, 0x75, 0x79, 0x7a, 0x7b and so on.


Note also the confusion/error in the description of the "tristate memory interface" configuration.

UG-214 3.3.7. As far as I can work out is the memory interface in tristate when sdp_io 0x2984] is "1"


Best regards,