This easily extendible example application implements a basic fan controller using a Raspberry Pi Pico.
- Pi Pico
- Temperature sensor (I use MCP9808)
- Computer PWM fan (I use 12v Noctua NF-A9)
- Buffer to bring logic to 5v (I use 74AHCT125)
- Power supply for the fan (12v in my case)
- USB power for the Pico
Optionally also a MOSFET to turn the fan off - if yours doesn’t reach 0 RPM at 0% PWM.
This repository provides a hardware-agnostic FanController object, and a Fan object for communicating with the fan using the RP2040 SDK. FanWithMOSFET is an untested extension of Fan for using a MOSFET (or relay) to shutdown the fan completely. TempSensor is an abstract class / interface for a temperature sensor: you need to provide code for communicating to your temperature sensor. /mcp9808.hpp is provided in this repository as an example.
.
├── CMakeLists.txt
├── main.cpp
├── mcp9808.hpp
├── README.org
└── src
├── fan_controller.cpp
├── fan.cpp
└── include
├── fan_controller.h
├── fan.h
└── temp_sensor.h
/main.cpp shows how I use the fan controller to communicate over USB serial to a Raspberry Pi running Home Assistant.
To modify the fan profile, edit the switch-case statement in src/fan_controller.cpp.