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External SDRAM doesn't work on 96kHz...


when I link my project (reverberation via SIMULINK embedded IDE link) it works fine on 48kHz, but when I try it on 96kHz it only talks thru...

thats why the data section for reverberation is on SDRAM....because for internal on-chip memory it is too large..

an other problem is that I try hard to flash the project....I use the default PROM > hex > 8bit > .ldr and flash it with the flash programmer successful...but it don't consider the SDRAM

see attachment for linker file..............

  • Hi,

    Can I ask you for some further details. You say that the application doesn't apply the reverberation when you place the reverb data on SDRAM - is this the case both when you run the application as a DXE, and when you try to boot the loader file?

    Does the same problem occur when using 48kHz if you place this data in SDRAM also? You can use the "#pragma section()" directive to force your data into SDRAM by doing something like the following in your code:

    #pragma section ("myData")

    int reverbData[10000] = {...};

    then in the LDF:



         INPUT_SECTIONS( $OBJECTS(seg_dmda) $LIBRARIES(seg_dmda))

         INPUT_SECTIONS( $OBJECTS(myData))

    } >MEM_sdram_32bit

    I believe from your other posts that you are using the 21369 EZ-KIT Lite. For this reason, I would recommend taking a look at the readme file for the Power On Self Test example, located in "...\213xx\Examples\ADSP-21369 EZ-KIT Lite\", which describes the steps to configure a loader file for this target. Note that you have to associtate the boot kernel file, 36x_prom.dxe with the Loader File in the project options.

    This boot kernel takes care of configuring the sdram, in "...\213xx\ldr\36x_prom\369_prom.asm\", from line 449 onwards.

  • Hi Craig....

    sorry for the wrong expression.... are right...I'm using ADSP-21369 EZ-KIT LITE 2.1 2006

    my project as executable file (.dxe) on 48kHz and on SDRAM it works fine....

    (the SIMULINK dsp.dlb(seg_dmda) is always on SDRAM, because it is too big for internal memory)

    but the same project on 96kHz talks through without signal processing (reverberation)

    (I switch to 96kHz in init1835viaSPI.c > DACFS96 and ADCFS96...I hope thats all for this purpose)

    now I suppose the SDRAM is too slow for 96kHz, but I don't hope so...

    okay the other thing with the flash I want to check up today/tomorrow....

    ps: there is the whole project as archive in attachment


  • Hi,

    It looks like your project links against some Matlab resources which I do not have on my PC, so I cannot build this application. As the 48kHz sampling rate uses SDRAM also, I believe we can rule out any problems with your project configuration causing the problem. Unfortunately, I cannot comment on whether it is a possibility for the SDRAM to be too slow for your application to work at 96kHz, however perhaps someone else on the forum may be able to offer further insight.



  • oh sorry...

    maybe i gave you the wrong version...with processor_in_the_loop_testing........

    here you get the right one...with dspsizeof_rt.h from matlab.....I guess this is what you need..

    furthermore you have to change the two "additional include directories" in "preprocessor" to your working path....and then it should work

    (I think you know it)

    flashing with SDRAM is still a problem....projects using no SDRAM flash and boot fine.

    I've checked the options and read the power_on_self_test README and all is set okay....


  • ChLatte wrote:

    @ CriagG please try again...

    Hi Christian,

    my apologies for the delay in replying to you. Using your updated example I was able to reproduce the behaviour you were reporting, when I set it to 96kHz (while the reverb could clearly be heard at 48kHz). Unfortunately I cannot offer anything further right now, but I have asked our Applications group to take a look, as they are better placed to advise what could be causing the problem at 96kHz.

    However, if the matter is urgent for you, I would recommend contacting private support, with a link to this thread, using the following URL:


  • This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin