README.md

Example module Microsoft.PowerShell.IoT.Fan

This PowerShell module is for turning on/off a fan on Raspberry Pi 4 case enclosure. This showcases GPIO functionality of the Microsoft.PowerShell.IoT module.

Hardware setup

This Raspberry Pi 4 case enclosure comes with a 5V fan that can be connected to Raspberry Pi 5V and GND pins. This fan is nice but a little noisy so we can use this example module to turn it off when the CPU temperature is relatively low. An IRLB8721 transistor can be used to switch power to the fan based on GPIO line of Raspberry Pi.

Wiring

Insert IRLB8721 transistor into the break of the negative wire of the fan. Connect transistor gate to GPIO 17 (BCM schema) on Raspberry Pi.

Software setup

Install PowerShell Core on Raspberry Pi

Installation instructions can be found here.

Start Powershell and install modules

pwsh

Install-Module -Name Microsoft.PowerShell.IoT

git clone https://github.com/PowerShell/PowerShell-IoT.git

Usage

# Start monitoring CPU temperature and turn on the fan when it reaches 71 degrees; turn fan off when CPU temperature drops below 55 degrees
pwsh ./PowerShell-IoT/Examples/Microsoft.PowerShell.IoT.Fan/SmartFan.ps1 -Pin 17 -OnTemperature 71 -OffTemperature 55 -TemperatureScale Celsius
VERBOSE: 1:36:05 PM: CPU temperature  =  71.575 C | 160.835 F
VERBOSE: Starting fan...
VERBOSE: 1:36:10 PM: CPU temperature  =  70.601 C | 159.0818 F
VERBOSE: 1:36:16 PM: CPU temperature  =  70.114 C | 158.2052 F
VERBOSE: 1:36:21 PM: CPU temperature  =  68.653 C | 155.5754 F
#...
VERBOSE: 1:39:01 PM: CPU temperature  =  55.504 C | 131.9072 F
VERBOSE: 1:39:06 PM: CPU temperature  =  55.504 C | 131.9072 F
VERBOSE: 1:39:11 PM: CPU temperature  =  54.043 C | 129.2774 F
VERBOSE: Stopping fan...
VERBOSE: 1:39:17 PM: CPU temperature  =  55.991 C | 132.7838 F
#...

This produces following CPU temperature graph: