Is it possible to use Klipper to talk to devices, specifically fans, connected to the USB ports of the host machine? I have a printer controlled from a Linux Mint laptop running Klipper which has plenty of ports to spare, but the driverboard for my printer has no more sockets for fans. As such, I w…

Normally a fan attached via USB only uses GND and +5V so you are not able to control it from the machine. If you have free driver ports on your MCU board you can install pin extender like the following: https://de.aliexpress.com/item/1005003754128206.html Those work pretty well!

For OctoPrint this was developed: [image] GitHub - jcassel/OctoPrint-Siocontrol: OctoPrint Plugin for Serial IO Control... OctoPrint Plugin for Serial IO Control like GPIO Control that adds a sidebar with on/off buttons and status for inputs for controlling outputs but also allows for m…

Unfortunately I don’t believe my board has the pins required for that module or other ones I have seen online Even if I cant fine tune the USB fans’ speeds, just having capability to say “turn on at layer 2” would be enough. Is this also not possible?

[image] Rudy_Manian: Is it possible to use Klipper to talk to devices, specifically fans, connected to the USB ports of the host machine? Not directly. Why don’t you use a pico as a second mcu? It’s quite inexpensive and has some GPIOs. [image] Raspberry Pi Pico + ADX…

Mostly because my familiarity with electronics and klipper is zero. This is my first printer, for context. I have managed to work around my issue by converting some unused LED headers on my printer’s control board to power the fans, which has worked well for me so far. The voltages and amperage pus…

Just curious. Can you explain exactly what you did?

There were LED ports on the board that use the same header (jst xh 2.54) and had the same voltage and current output as the fans I needed. So I just found what pins they used and assigned them as fans in my printer.cfg file.

Do yourself a favor and start reading here RPi microcontroller - Klipper documentation The link from Sineos I posted above might bring you faster to your goal. Right now you are going down the wrong path.

Eventually I probably will, but for now this workaround suits my needs. I think as I upgrade my printer more and more I will start doing the things the right way haha

[image] Rudy_Manian: There were LED ports on the board that use the same header (jst xh 2.54) and had the same voltage and current output as the fans I needed. This is a perfectly fine and correct approach. The alternative as mentioned @hcet14 is valid as well but requires more effort since …

Controlling Host Machine USB Ports

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hcet14 November 20, 2023, 7:18pm 5

Not directly.

Why don’t you use a pico as a second mcu? It’s quite inexpensive and has some GPIOs.

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Controlling Host Machine USB Ports

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