# Controlling LED brightness using node-red-node-pi-gpio with pwm results in flickering

**URL:** https://discourse.nodered.org/t/controlling-led-brightness-using-node-red-node-pi-gpio-with-pwm-results-in-flickering/81680
**Category:** Core Development
**Tags:** docker
**Created:** [30 September 2023 08:32 UTC](https://discourse.nodered.org/t/controlling-led-brightness-using-node-red-node-pi-gpio-with-pwm-results-in-flickering/81680 "2023-09-30T08:32:31Z")
**Posts on this page:** 1
**Showing post:** 6

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### Author: ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)
#### Post date: [30 September 2023 10:42 UTC](https://discourse.nodered.org/t/controlling-led-brightness-using-node-red-node-pi-gpio-with-pwm-results-in-flickering/81680/6 "2023-09-30T10:42:51Z")

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Apparently pigpio PWM uses DMA.  
[https://www.js4iot.com/2021/06/04/DMA\_PWM-PIGPIO.html](https://www.js4iot.com/2021/06/04/DMA_PWM-PIGPIO.html)

@dceejay says he expects GPIO nodes to stop working (presumably when RPiOS is updated for the Pi 5) [https://discourse.nodered.org/t/raspberry-pi-5-announced-today-available-oct-23/81656/5](https://discourse.nodered.org/t/raspberry-pi-5-announced-today-available-oct-23/81656/5) so it looks like switching to node-red-node-pi-gpiod is essential.

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