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.

AM62A3: How to time synchronize with processor, WL1831MOD, and external device

Part Number: AM62A3
Other Parts Discussed in Thread: WL1831MOD, , CC3301

Tool/software:

Hi TI Team,

 

My goal is to time synchronize a collection of embedded Linux boards that contain the AM62A3 processor, WL1831MOD, and external device and have a few questions on how to achieve it.

 

For the embedded Linux boards, the plan is to use the AM62A3 processor and WL1831MOD to execute the “Precise Time Synchronization Over WLAN” method described in the SWAA162A TI’s application report.  This is where my questions start,

 

  • Is it correct to assume the “Precise Time Synchronization Over WLAN” method will sync the Cortex-A53 (running the Linux OS)?
  • SWAA162A TI’s application report describes using WL1831MOD’s Pin 2 (GPIO11 - COEX_MWS_FRAME_SYNC) to AM335 ‘s GPIO 2_2 (TIMER4). What pin on the AM62A3 should WL1831MOD’s Pin 2 be routed to? Or can you describe how AM335 ‘s GPIO 2_2 (TIMER4) was selected?
  • Can the AM62A3‘s Time Sync Router be used to sync the AM62A3’s processor clock to an external device? For example, use the Time Sync Router send a periodic pulse to the external device?

 

Thanks,

Mike E

  • Hello Mike,

    I am going to start by sending you to the WL1831MOD team to discuss time sync with their device.

    You can find some information about sending PPS signals out through the time sync router in the Linux PTP documentation:
    https://software-dl.ti.com/processor-sdk-linux/esd/AM62AX/09_02_00/exports/docs/linux/Foundational_Components/Kernel/Kernel_Drivers/Network/CPSW-PTP.html

    Regards,

    Nick

  • Thanks Nick,

    The link provided gives me insight for how my application will interface with the CPTS module to generate a PPS and also timestamp external events (external devices generates a PPS to processor).

    When you said "start by sending you to the WL1831MOD team to discuss time sync" does that mean I need to create a post on their forum or you notified the  WL1831MOD team to respond to this post?

    Thanks,

    Mike E

  • Hi Mike,

    Sorry for the delay.

    Is it correct to assume the “Precise Time Synchronization Over WLAN” method will sync the Cortex-A53 (running the Linux OS)?

    Yes, this is an operation that runs on the wl18xx linux kernel driver

    SWAA162A TI’s application report describes using WL1831MOD’s Pin 2 (GPIO11 - COEX_MWS_FRAME_SYNC) to AM335 ‘s GPIO 2_2 (TIMER4). What pin on the AM62A3 should WL1831MOD’s Pin 2 be routed to? Or can you describe how AM335 ‘s GPIO 2_2 (TIMER4) was selected?

    There is no relation to a physical timer, it is just a GPIO. So you can use any available GPIO pin on the AM62A3.

  • Hi Sabeeh,

    Thanks for the information! After doing a deep dive into the topic, I realized there is a software issue using the AM62A3 processor and WL1831MOD. The AM62A3 PROCESSOR-SDK-LINUX-AM62A Version: 10.00.00.08 is using the Linux kernel v6.6 and the WL18 driver v8.8 is built for the Linux kernel v4.19. So I will not be able to use the AM62A3 processor and WL18 chip unless the wifi driver is updated. So, I will just have to use the CC3301 wifi chip and another method for time synchronization and mesh networking.

    Mike E