# Toggling of GPIO4\_IO23 on humming board pulse **URL:** \ **Category:** NXP i.MX8M Plus\ **Created:** [October 9, 2023, 1:35pm UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737 "2023-10-09T13:35:10Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Kartheek](https://avatars.discourse-cdn.com/v4/letter/k/b4bc9f/32.png) [@Kartheek](https://community.solid-run.com/u/Kartheek)\ **Post date:** [October 9, 2023, 1:35pm UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/1 "2023-10-09T13:35:10Z")
Hi, I want to toggle the gpio pin 119 attached in screen shot. But not able to toggle when i see on oscilloscope/multimeter. Can you please correct me if i am wrong? I followed the below steps to toggle it. 1. echo 119 \> /sys/class/gpio/export 2. echo out \> /sys/class/gpio/gpio119/direction 3. echo 1 \> /sys/class/gpio/gpio119/value 4. echo 0 \> /sys/class/gpio/gpio119/value Thanks, Kartheek ![Screenshot from 2023-10-09 19-03-38](https://europe1.discourse-cdn.com/flex005/uploads/solid_run/original/1X/ee71ff973df646fd49d15ca6b82ee9b036347f8b.jpeg) ---
**Author:** ![jnettlet](https://dub1.discourse-cdn.com/flex005/user_avatar/community.solid-run.com/jnettlet/32/62_2.png) [@jnettlet](https://community.solid-run.com/u/jnettlet)\ **Post date:** [October 10, 2023, 3:37pm UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/2 "2023-10-10T15:37:25Z")
What BSP image are you running? ---
**Author:** ![Kartheek](https://avatars.discourse-cdn.com/v4/letter/k/b4bc9f/32.png) [@Kartheek](https://community.solid-run.com/u/Kartheek)\ **Post date:** [October 11, 2023, 5:51am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/3 "2023-10-11T05:51:23Z")
Hi Please see the metioned screen shot for Linux BSP version. And i have followed the steps mentioned in link for [yocto](https://solidrun.atlassian.net/wiki/spaces/developer/pages/287212276/i.MX8M+Mini+Yocto) Thanks & Regards, Kartheek ![Screenshot from 2023-10-10 15-03-43](https://europe1.discourse-cdn.com/flex005/uploads/solid_run/original/1X/8f120ce6694bb157d9cc2dd79bfd569b1f6ee9b7.png) ---
**Author:** ![jnettlet](https://dub1.discourse-cdn.com/flex005/user_avatar/community.solid-run.com/jnettlet/32/62_2.png) [@jnettlet](https://community.solid-run.com/u/jnettlet)\ **Post date:** [October 11, 2023, 7:37am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/4 "2023-10-11T07:37:12Z")
and what revision of the carrier are you using? The pin connected to the mikrobus changed between rev 2.3 and rev 2.5 carriers ---
**Author:** ![Kartheek](https://avatars.discourse-cdn.com/v4/letter/k/b4bc9f/32.png) [@Kartheek](https://community.solid-run.com/u/Kartheek)\ **Post date:** [October 11, 2023, 9:16am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/5 "2023-10-11T09:16:15Z")
May i know how to find the rev. I have rev 2.2, 2.3 & 2.5 downloaded from this [link](https://solidrun.atlassian.net/wiki/download/attachments/262144001/HummingBoard%20iMX8%20Schematics.zip?api=v2). And we are following rev 2.5. ---
**Author:** ![jnettlet](https://dub1.discourse-cdn.com/flex005/user_avatar/community.solid-run.com/jnettlet/32/62_2.png) [@jnettlet](https://community.solid-run.com/u/jnettlet)\ **Post date:** [October 11, 2023, 9:17am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/6 "2023-10-11T09:17:26Z")
You should be able to check the SKU, but otherwise it is silk screened onto the board underneath where the SOM is mounted. ---
**Author:** ![Kartheek](https://avatars.discourse-cdn.com/v4/letter/k/b4bc9f/32.png) [@Kartheek](https://community.solid-run.com/u/Kartheek)\ **Post date:** [October 11, 2023, 9:48am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/7 "2023-10-11T09:48:26Z")
Unable to find the rev. Attached board underneath image for your refernce. Can you please help me. ![MicrosoftTeams-image](https://europe1.discourse-cdn.com/flex005/uploads/solid_run/original/1X/fdc32b8e7677f1d576623c80ad88676b0d1d94cd.jpeg) ---
**Author:** ![jnettlet](https://dub1.discourse-cdn.com/flex005/user_avatar/community.solid-run.com/jnettlet/32/62_2.png) [@jnettlet](https://community.solid-run.com/u/jnettlet)\ **Post date:** [October 11, 2023, 10:18am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/8 "2023-10-11T10:18:57Z")
It is on the top of the board in between the SOM connectors. You need to remove the SOM to see it. ---
**Author:** ![Kartheek](https://avatars.discourse-cdn.com/v4/letter/k/b4bc9f/32.png) [@Kartheek](https://community.solid-run.com/u/Kartheek)\ **Post date:** [February 6, 2024, 4:05am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/9 "2024-02-06T04:05:35Z")
Hi Jnettlet. Sorry for late response. My humming board pulse(imx8mplus) is rev 2.5. Can you please tell how to toggle gpio on mikrobus. ---
**Author:** ![jnettlet](https://dub1.discourse-cdn.com/flex005/user_avatar/community.solid-run.com/jnettlet/32/62_2.png) [@jnettlet](https://community.solid-run.com/u/jnettlet)\ **Post date:** [February 7, 2024, 8:33am UTC](https://community.solid-run.com/t/toggling-of-gpio4-io23-on-humming-board-pulse/737/10 "2024-02-07T08:33:14Z")
Rev 2.5 has the SAI2\_RXD pin connected to SAI3\_RXD of the iMX8MP SOM. This pin is also shared with the wm8904 audio so they can’t be used at the same time. To use this pin as a GPIO you need to remove it from the &pinctrl\_sai3 group and add it to the &pinctrl\_hog group as a GPIO. It should be GPIO 158.