Hi,
We want to determine the DDR/EMIF/PLL AM57x registers values for the our design. and we are following guidelines in SPRAC36 which provides instruction on using spreadsheet program – SPRAC36_EMIF_RegisterConfig_v2.xls
Ideally, the plan to have two different configurations..
Config 1) AM5728 ( EVMs / some KA Boards) @ 1066MHz Data Rate
Config 2) AM5718 ( EVMs / some KA Boards) @ 1333MHz Data Rate ( to maximize memory bus capability)..
Our Design uses two 4Gb Micron Part # MT41K256M16TW-107P , which is a 1866 speed grade part ( Note that the CL for 1866 is 13, I will use these values later in the spreadsheet for our product )
The TI provided spreadsheet file SPRAC36_EMIF_RegisterConfig_v2.xlsm come pre-loaded with parameters..
Looking at the Step 1- System detail tab, the DDR freq is 532 (Detail #6), the speed grade is 1006(Detail #11) and CAS Latency(Detail #14) is 7. – see below…
Going over to the Step 3- DDR timing tab page, the CAS Latency cell has a value of 7 ( this is the correct value for the above settings but it can changed to 8 which is also a valid setting). The AM57x tool is working properly.
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Switching the discussion over to our specific product design.. and assuming design config # 2 ( note same problem in design config #1 too) above: AM5718 @ 1333MHz data rate .
As mentioned, our design will use Micron Part # MT41K256M16TW-107P , which is a 1866 speed grade part ( Note that the CL @ 1866MHz is 13, I will now use these values in the spreadsheet)
. Looking at the Step 1- System detail tab page in the spreadsheet file SPRAC36_EMIF_RegisterConfig_v2 _SAGE_AM571x_667MHz_4Gb_rev1.xlsm ( I am unable to attach a .xlsm file here but can email it if requested) The DDR freq is 667 (Detail #6), the speed bin is 1833(Detail #11) and CAS Latency(Detail #14) is 13. for our design is entered below along with our other specifics.
Going over to the Step 3- DDR timing tab page, all of our design settings ( DDR timing) can be changed to the proper values except for the CAS Latency which is stuck at ‘7’.. I get the window popup when I try any value other than 7 ( see picture below when I try to enter the value 9) . Doing some experimentation, the problem seem to be related to the DDR 1866M data rate of the memery we are using.
My question is … Is there a bug in the program in the CAS LATENCY cell operation or did I make in a mistake in setting some other input parameter ..
I can certainly work around the problem by manually changing the CL field in the SDRAM Config Register 0x4C00_0008
Thanks for your assistance in this matter.
Larry
