Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
Collapse
Brand Logo

ModalAI Forum

  1. ModalAI Support Forum
  2. Software Development
  3. VOXL SDK
  4. Speeding up GPIO Write Time

Speeding up GPIO Write Time

Scheduled Pinned Locked Moved VOXL SDK
2 Posts 2 Posters 502 Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • Ritwik MajumdarR Offline
    Ritwik MajumdarR Offline
    Ritwik Majumdar
    wrote on last edited by
    #1

    In the VOXL documentation, it states that the gpio pin must already be opened and that libvoxl_io must be preloaded to acheive the 1-2 ms call time.

    Does the VOXL 2 library (libqrb5165-io) suffer from this same problem? If so, how do I get to the fast call time?

    Alex KushleyevA 1 Reply Last reply
    0
    • Ritwik MajumdarR Ritwik Majumdar

      In the VOXL documentation, it states that the gpio pin must already be opened and that libvoxl_io must be preloaded to acheive the 1-2 ms call time.

      Does the VOXL 2 library (libqrb5165-io) suffer from this same problem? If so, how do I get to the fast call time?

      Alex KushleyevA Offline
      Alex KushleyevA Offline
      Alex Kushleyev
      ModalAI Team
      wrote on last edited by
      #2

      @Ritwik-Majumdar

      The delay of VOXL2 control has not been tested, but it should be relatively small (1ms or less)

      You can control the GPIO directly from command line, see

      • https://docs.modalai.com/voxl2-linux-user-guide/#gpios
      • https://docs.modalai.com/voxl-gpio-io/#manipulating-gpio-using-linux-commands

      Please take note of the GPIO pin numbering : the GPIO have an offest of 1100 (e.g. GPIO 84 = 1184)

      Setting CPU to perf mode (voxl-set-cpu-mode perf) will speed things up.

      You can time the execution time (i just did in perf mode). Sometimes 0.000s, sometimes 0.001s, so somewhere around 1ms. You can do more precise timing if needed.

      voxl2:/$ time echo 1 > /sys/class/gpio/gpio<GPIO_NUM>/value
      
      real	0m0.001s
      user	0m0.000s
      sys	0m0.000s
      
      1 Reply Last reply
      0

      Hello! It looks like you're interested in this conversation, but you don't have an account yet.

      Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.

      With your input, this post could be even better 💗

      Register Login
      Reply
      • Reply as topic
      Log in to reply
      • Oldest to Newest
      • Newest to Oldest
      • Most Votes


      ModalAI
      Categories Recent Tags ModalAI.com Docs
      © 2026 ModalAI® · Accelerating autonomy for smaller, smarter, safer drones · Powered by NodeBB
      • Login

      • Don't have an account? Register

      • Login or register to search.
      • First post
        Last post
      0
      • Categories
      • Recent
      • Tags
      • Popular
      • Users
      • Groups