• State Resolved
  • Locked Locked
  • Replies 11 replies
  • Subscribers 102 subscribers
  • Views 495 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS320C6727B: WE toggle twice in 1 write cycle

Shine
Genius 13655 points
Part Number: TMS320C6727B

Hello Champs

Customer connected SST39VF800A to EMIF, the circuit is below.

The code is below:

void main()
{
    initSystem();                           //系统初始化
    A1CR = 0x3FFFFFFD;          //flash时序寄存器配置
    M0PDOUT = 0x10000001;    //将AXR0配置为高电平
    while(1)
    {
        Flash_5555h = 0xAA; //向DSP地址0x9000AAAA处(即Flash的0x5555处)写0xAA
        Delay(20);
    }


But he found the WE is toggled twice in one write cycle and the BA0 is not correct. Please see below snapshot.

Blue: EM_CLK 55MHz
Yello: WE
Green: CE

Thanks.
Rgds
Shine

  • 0
    TI__Mastermind 26245 points

    This is an older device and may take some time to try and get an answer.

    --Paul

  • 0
    TI__Guru* 77650 points

    Shine, can you dump all of the EMIF register configuration, as show in EMIF user's guide.  There may be something wrong with your configuration

    Regards,

    James

  • 0 in reply to JJD
    TI__Genius 13655 points

    Hello James,

    Thanks for your help.

    Below is the configuration of EMIF registers.

    SDTIMR = 0x31114610;
    SDSRETR = 0x1F;
    SDRCR = 0x9C4;
    SDCR = 0x4721;
    Delay(1100);
    SDRCR = 0x61A;

    A1CR = 0x3FFFFFFD;

    Thanks.
    Rgds
    Shine



  • 0 in reply to Shine
    TI__Guru* 77650 points

    Shine, it appears to be working in 8bit mode.  Can you read out the register value for A1CR (not just what is configured in code)?  It may not be getting written correctly.

    Also, how is variable Flash_5555h declared?  Is it defined as a byte (8bit) or word (16bit) element?

    Regards,

    James

  • 0 in reply to JJD
    TI__Genius 13655 points

    Hi James,

    Thanks for your help.

    1. Yes, customer printf the A1CR register, it shows the value is 0x3FFFFFFD

    2.Flash_5555h is defined as below：

    #define Flash_5555h         *(unsigned int *)0x9000AAAA

    Thanks.
    Rgds
    Shine

  • 0 in reply to Shine
    TI__Guru* 77650 points

    Shine, can you show the processor side of the schematic connection?  Are you showing signal EM_WE or EM_WE_DQM in the scope shot?

    Regards,

    James

  • 0 in reply to JJD
    TI__Genius 13655 points

    Hi James,

    Thanks for your help.

    (1) Below is the processor side of the schematic connection.

    Flash_CE pin is connected to CS2 through FPGA VHDL code. 
    CS_2 <= FLASH_CE;

    Because DSP is BGA package, he used VHDL code to connect the EMIF pin to FPGA and observe the timing wave on FPGA side.

    (2) It shows EM_WE in the scope shot.

    Thanks.
    Rgds
    Shine

  • 0 in reply to Shine
    TI__Guru* 77650 points

    Shine, i'm not sure what is going on here.  Does the write complete successfully?  Does the same behavior happen on a read?

    REgards,

    James

  • 0 in reply to JJD
    TI__Genius 13655 points

    Hi James,

    Thanks for your help.

    1.  The read operation failed, too. 

    2. Because he failed to write data to fixed address, so he can't read data correctly. But the read timing wave is the same to the write timing wave. 

    Thanks.
    Rgds
    Shine



  • +1 in reply to Shine
    TI__Guru* 77650 points

    Shine, is it possible that your compiler is expecting the  *(unsigned int *) to be a pointer to a 32-bit value?  So when you perform the write, it is actually performing 2 16-bit writes.  That seems to be what the waveforms are indicating.  Can you try declaring the variable as an (*unsigned short *) ?  You may need to inspect the assembly code produced by the complier to ensure it is performing the correct amount of writes.

    Regards,

    James

  • 0 in reply to JJD
    TI__Genius 13655 points

    Hi James,

    Customer resolved the issue according to your advice.

    Thanks.
    Rgds
    Shine