mddr problem with am3352

Thank you,the problem solved.

another problem ,

I 'm debugging the program with CCSv5, after I configure the EMIF, then open the memory window,it was located in the mddr space and enable continuous refresh button, found that some bytes changed at every refreash time, and if I change the value of  an address, the value of other address also changed, not a specific address, I have test a lot of times, 

 most of the contents are 0xFF.

which registers should i adjust?

It looks like you don't have your AC timings or DDR PHY registers setup correctly.  Please review the following wiki: 

http://processors.wiki.ti.com/index.php/AM335x_EMIF_Configuration_tips

regards,

James

yeah, i have followed the tips,but it's still got the problem.

i'll try different phy and ac timing

are you meaning the problem of ccs？

I have followed the tips,followed the caculate tools, seed spreadsheet. but still got the problem

the following is the picture of the momery. The red indicates the changed(because I have enable the continuous refresh) ,the address changed was randomized,

And if Changed the value of somewhere, the value of other place may be changed, this is what i saw.

in the tips, there are two cases between DDR_CK length and DDR_DQS length, but what will be result if DDR_CK length equal to DDR_DQS length?

Could you help me figure it  out?

thank you very much

I try to use different SDRAM drive strength, see the following picture:

FULL drive strength:

1/8 drive strength:

I have write the 0x12345678 to 0x80000000 and 0xdeadbeef to 0x8000000C.

the red shows the change between a second before, I think FULL drive strength may be better than 1/8 drive strength,  because in am335x-evm, after initial the DDR2, the contents are different each other,it couldn't be 0xFF mostly.

Is that right? how to improve the drive strength?