PetrozPL

Good to hear that someone still finds it useful

Please, post pictures with your FAN connection to the board. EDIT : I've just checked and FAN in okdo is only 2-wire: so to control it's speed via PWM you have to add additional circuit like on this page : https://forums.raspberrypi.com/viewtopic.php?t=194621&start=50 You need to connect GPIO wire to either PWM0 or PWM1 (one you would like to use to control FAN speed). Without this additional circuit you can't change the speed of 2-pin FAN. The other option is to buy the 3-pin FAN for 5V with additional speed control wire.

Hi, I'm new to armbian and I've started with RockPi4b board. I would like to add fan control with PWM, but adding pwm (or pwm0) overlay doesn't work. I can't also find the overlay for it at /boot/dtb-5.8.6-rockchip64/rockchip/overlay/. Is it supported? I've checked and the /sys/class/pwm/pwmchip0 is present, but accessing export, as described here : doesn't work and /sys/class/pwm/pwmchip0/pwm0 is not present. I've tried to find pwm access examples for this board, but none of it works on armbian (all are vendor builds specific). Can anybody point me in the right direction or give any hint how to enable pwm? EDIT : I've managed to enable/dosable PWM pin with sudo mraa-gpio set 11 1 Although, its GPIO, rather PWM access so I can't control the FAN speed and only power on/off the fan.