ESP32 Forum

Hi all,
I just started my esp32 and I'm having fun with ulp for low power work.

I'm using a dev board and a lolin32. I'm trying to blink board led.

Dev board with led on GPIO4 is working well, but I have no success with lolin32 and led on GPIO22.

1st question: can ulp drive GPIO22 in output ?
2nd question: can ulp drive every pin in output ?

TIA
ng

Hello ng

1. No, ULP cannot drive GPIO22

2. No. Please check the Pin description here: https://www.espressif.com/sites/default ... eet_en.pdf

In the 'Function' column find the GPIO you're interested in and then check if there is a corresponding RTC_GPIO listed. If yes, ULP can drive it. So for instance GPIO4 equals RTC_GPIO10 and ulp can drive it. However GPIO22 doesn't have an RTC alternative, that's why it cannot be use from ULP.

Cheers
Felix

Hi felmue, thanks for info!