I want to make an irrigation system (more like a mist-sprayer) for a little terrarium I have, and I'm planning everything I'll need.
So I've found a little usb water pump.
As this would be automated with a humidity sensor, I need to be able to turn on/off the water pump.
I've seen online that usb ports can be powered off/on the rpi 3b+ using https://github.com/mvp/uhubctl
But I want to make sure and ask you guys. Thanks
Re: How to toggle on/off a usb device on rpi 3b+
The Pi can only toggle power to all 4 ports together. You can't control individual ports so any other USB device plugged in will also be turned off. If that is okay then you can use uhubctl.
Re: How to toggle on/off a usb device on rpi 3b+
Well I plan on hooking up some fans to allow for airflow inside the chamber, but I guess I can do that with the GPIO pins so that is not a problem.
Thanks
Re: How to toggle on/off a usb device on rpi 3b+
Re: How to toggle on/off a usb device on rpi 3b+
That was what I was planning, but maybe I can use 4 of those raspberry small 5V fans and that will be enough.ejolson wrote: ↑Mon Jul 06, 2020 4:37 pmHow will you hook a fan to GPIO? Will you use some sort of transistor?
Re: How to toggle on/off a usb device on rpi 3b+
If you connect even the smallest fan to a GPIO pin, the Pi will cease to work.
It is possible to connect fans to the 5V power on the GPIO header, but then they can't be turned on or off. If you want them always on, it's better to connect the fans to a separate power supply.
Re: How to toggle on/off a usb device on rpi 3b+
Just FYI. Do not try to reduce fan speed/noise by wiring them to the 3.3V pin. You can kill the Pi by doing that.
Re: How to toggle on/off a usb device on rpi 3b+
Hmmm I'd like to be able to turn them on/off.ejolson wrote: ↑Mon Jul 06, 2020 4:46 pmIf you connect even the smallest fan to a GPIO pin, the Pi will cease to work.
It is possible to connect fans to the 5V power on the GPIO header, but then they can't be turned on or off. If you want them always on, it's better to connect the fans to a separate power supply.
How could I do it then?