• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Subscribers 97 subscribers
  • Views 320 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

AM3352: When the CPU transfers data from USB FIFO to DDR2, the speed becomes very slow.

Sh.Sasaki
Guru 13625 points
Part Number: AM3352

Hi everyone, 

When the CPU transfers data from USB FIFO to DDR2, the speed becomes very slow.

  • When reading and discarding the data of USB FIFO by CPU, it is 15 ~ 19MB / s.
  • When transferring data from USB FIFO to DDR2 by CPU, it is 1.5 ~ 1.6MB / s.

I would like to know why data transfer to DDR would slow down to 1/10 this way.
The PLL sets L3F_CLK to 200 MHz and L2S_CLK to 100 MHz.

Best regards,

Sasaki

  • 0
    TI__Guru**** 393215 points
    Hi,

    Please post what software you are using, and which version.
  • 0 in reply to Biser Gatchev-XID
    Guru 13625 points

    Hi  Biser-san,

    My customer's SW is below.

    • processor_sdk_rtos_am335x_3_02_00_05
    • pdk_am335x_1_0_5
    • StarterWare 02. 01. 01. 01

    My customer is customizing the program based on Starterware.

    Best regards,

    Sasaki

  • 0 in reply to Sh.Sasaki
    TI__Guru* 95265 points
    Hi,

    The StarterWare is already obsolete, are you able to try the latest Processor SDK RTOS on AM335x? What is the MMU setting for the DDR2 and USB region? Is this a bulk or MSC example? Is the CPU speed is low, are you able to enable the DMA?

    Regards, Eric
  • 0 in reply to lding
    Guru 13625 points

    Hi Eric-san,

    Thank you for your advice.

    My customer's USB application is CDC.

    lding said:


    The StarterWare is already obsolete, are you able to try the latest Processor SDK RTOS on AM335x? What is the MMU setting for the DDR2 and USB region? Is this a bulk or MSC example? Is the CPU speed is low, are you able to enable the DMA?

    I confirm this to my customer and I organize this issues and post again.
    Therefore, please close this thread once.

    Best regards,

    Sasaki

  • 0 in reply to Sh.Sasaki
    TI__Guru* 95265 points
    Sasaki,

    Thanks for the info! The Processor SDK RTOS doesn't support CDC, (it only supports MSC and bulk so far, HID and CDC are planned). So this is a gap. Not sure how your customer can update the USB with processor SDK, and how to support the CDC issue if they have to use Starterware.

    Regards, Eric