• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 2 answers
  • Subscribers 83 subscribers
  • Views 746 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.

TMS320F28388S: EtherCAT related configuration

Linda Zhang84708
Expert 6720 points
Part Number: TMS320F28388S


Hello Champs,

Customer is using F28388S EtherCAT function and has some questions as below:

1) Regarding external EEPROM needed by F28388S ESC, is there any special resource requirement for it such as capacity etc.? Shall we have recommendation for this EEPROM selection?

2) What about the difference of pin108 (ECS_LED_STATE_RUN) and pin107 (ECS_LED_RUN)? How to design the connection of pin108? 

3) In datasheet pin155 (ECS_TX0_CLK) has been marked with "I" (input), is its direction wrong?

4) Is it OK to use pin90 (ESC_PHY_CLK) as output and provide clock for external PHY chip so that additional external oscillator for PHY chip can be unnecessary?

Would you please kindly help? Thanks!

Best Regards,

Linda

  • 0
    TI__Guru** 115881 points

    Linda,

    I'll try to reply on two of your queries -

     3) In datasheet pin155 (ECS_TX0_CLK) has been marked with "I" (input), is its direction wrong?

    This is input only. This is clock from PHY to controller.

     4) Is it OK to use pin90 (ESC_PHY_CLK) as output and provide clock for external PHY chip so that additional external oscillator for PHY chip can be unnecessary?

    EtherCAT interface has specific requirement for PPM for clock to PHY so user need to do extensive testing of this with complete system to make sure it works fine. Our recommendation is to use 25MHz clock for PHY as well as device (still single XTAL) when using EtherCAT. 

    We'll have other expert reply to two other queries.

    Regards,

    Vivek Singh

  • 0
    TI__Mastermind 42195 points

    Linda,

    Linda Zhang84708 said:
    1) Regarding external EEPROM needed by F28388S ESC, is there any special resource requirement for it such as capacity etc.? Shall we have recommendation for this EEPROM selection?

    For the ESC, only a few things are stored in there. its only a few words of configuration data. If you look at what we program in our EtherCAT's SSI EEPROM its less than ~100 words. This is just configuration data for the ESC. I am not an EtherCAT expert, but I don't know of another use for this EEPROM.  

    Here is where Beckhoff explains the memory structure of the EEPROM. https://infosys.beckhoff.com/english.php?content=../content/1033/tc3_io_intro/1358008331.html&id=5054579963582410224 

    Linda Zhang84708 said:
    2) What about the difference of pin108 (ECS_LED_STATE_RUN) and pin107 (ECS_LED_RUN)? How to design the connection of pin108? 

    This is a tricky naming convention. Please see the beckhoff documentation here: https://download.beckhoff.com/download/Document/io/ethercat-development-products/ethercat_esc_datasheet_sec1_technology_2i3.pdf 

    I believe this along with Vivek's reply should answer all of your questions!

    Regards,
    Cody 

  • 0 in reply to Cody Watkins
    TI__Expert 6720 points

    Hello Vivek, Hello Cody,

    Thank you for your kind help. It's clear.

    Customer still had below questions:

    1) For SYNC0/SYNC1 signals in F28388S ESC, how to design its connection?

    2) Does DP83822 pin24 need to be connected with F28388S ESC_PHYx_LINKSTATUS pin? If yes, is the external pull-up resistor necessary on this pin?

    Would you please kindly help? Thanks!

    Best Regards,

    Linda

  • 0 in reply to Linda Zhang84708
    TI__Expert 4610 points

    Linda,

    Please find the answers below

    1) For SYNC0/SYNC1 signals in F28388S ESC, how to design its connection?               

    SYNC0/1 output signals are typically used for synchronous generation of output signals across all the slaves in distributed clock environment. If you don’t have such requirement to generate an synchronized output, it can be left unconnected

    2) Does DP83822 pin24 need to be connected with F28388S ESC_PHYx_LINKSTATUS pin? If yes, is the external pull-up resistor necessary on this pin?

    The LED_0 of the phy which indicates the status of the link has to be connected to the ESC_PHYx_LINKSTATUS pin of the ESC. 

    Regards,
    Praveen