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CCS/CCSTUDIO-KEYSTONE: CCS can't read register value alway 0 in debug mode.

Part Number: CCSTUDIO-KEYSTONE

Tool/software: Code Composer Studio

HI, TI experts,

CCS 7. 4    SOC,TDA2eg-17

when I debug dsp edma, I found CCS can't read EDMA registers. It is alway 0.

  • Hi,

    According to the device's TRM, I can tell the addresses of the registers are in the correct place. 

    In this case, CCS may be unable to read memory mapped registers in the conditions mentioned in the post below:

    https://e2e.ti.com/support/tools/ccs/f/81/p/900857/3330666#3330666

    If none of these options apply to your case, can you be sure there is no memory management or protection mechanism in place? This may prevent accessing the specific addresses as they are remapped to other regions. 

    I will try to find additional scenarios and report back in case I find anything relevant. 

    Hope this helps,

    Rafael

  • Rafael,

    thanks for reply.

    I have read the link you supplied. I have no these condition, because my code worked well ,dsp edma worked well. just can't read these registers from CCS. 

    In addtion, I used "ti-processor-sdk-rtos-automotive-dra7xx-evm-04.03.00.05" sdk, and DSP run sys/bios OS. the demo code is apart of EDMA_LLD.

  • in addtion, I am not sure if  there is memory management or protection mechanism in place. I only worked on DSP, I know nothing about  A15 core running linux. maybe, A15 should do something?

  • Hi,

    Unfortunately I don't have the same board as you, but I am trying to find an example that uses EDMA on the C66x DSP for my AM574x IDK. 

    At this time I see the same as you (all zeros on the registers), but I need to figure out the example first. 

    Regards,

    Rafael

  • Rafael,

    I think you can use EDMA_LLD examples in "C:\ti\edma3_lld_2_12_05_30C\examples\edma3_driver\src". notes, we use EDMA1 (DSP EDMA 0x01D1 0000).
    waiting for your good news.

    Regards,

  • Hi,

    I could not create a testcase yet that modifies the addresses you show, but I see the Memory Browser shows data at 0x01D10000 location as shown in the screen below:

    In this case, I can't yet see if there is a problem itself with the Memory Browser. However, there is a secondary issue with the Registers view (no data is showing properly) and we are analyzing this. 

    Regards,

    Rafael

  • Hi,  Rafael

    I conside it may be EDMA register feature, Please deliver to EDMA experts. thanks.

    Regards,

    tao