PWM Output from PX4 DSP for servo control



  • Hello,
    Thank you for releasing most awaited VOXL 2 platform. We have placed an order for VOXL 2 and should receive the same within few days.

    We are working on Coaxial helicopter airframe on PX4 with VOXL-1 (We have VOXL 1 with us) and it had direct PWM lines for integrating servo needed for coaxial helicopter airframe. After going through VOXL 2 documentation I am bit worried about direct PWM control of servos since PX4 is now operating on RB5 DSP. I am aware of using MODALAI UART ESC for operating BLDC motors. Here are my queries.

    • How to get direct PWM control of servo from VOXL-2 ?

    • Can ModalAI ESC be used somehow for direct PWM servo control?


  • Dev Team

    @Aks We will be offering a small add on board to enable PWM output for ESC control. The hardware is ready and has been tested with other PX4 flight controllers but software support for it on VOXL 2 is still being completed. Once this is ready we will make an announcement and will offer the new add on board for sale on our web store. Thanks for your patience on this, we know it is a popular request from our customers.



  • @Eric-Katzfey Thank you for the great news.

    Any tentative timelines for release of this add-on board?


  • Dev Team

    @Aks I'd estimate about a month from now.


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