Getting Started with GreatFET

Follow these instructions to get started with GreatFET on Linux.

Install or Update Software

pip3 install --upgrade --user greatfet

Pay attention to the output of pip3 because it may tell you that you need to add something to your PATH.

Install udev Rules

This is an important step that we recommend so that you will be able to use your GreatFET as a non-root user. The example udev rules file that we provide assumes that your user is a member of the plugdev group. If that is not the case, you can either add your user to the plugdev group or modify the file to give permission to the group of your choice instead of plugdev.

This is not necessary on MacOS-based systems.

sudo wget https://raw.githubusercontent.com/greatscottgadgets/greatfet/master/host/util/54-greatfet.rules -O /etc/udev/rules.d/54-greatfet.rules
sudo udevadm control --reload-rules

Connect your GreatFET One

Find the USB0 port on your GreatFET One. This is the port on the left (convex) side of the board, the side with LEDs and buttons. Use a USB cable to connect this port to your host computer.

If you chose to install the udev rules and your GreatFET One was already connected to your computer prior to this step, take this opportunity to disconnect your GreatFET one from your computer and connect it again. This will ensure that the udev rules take effect.

Check your GreatFET One

Once connected, your GreatFET One should start to slowly flash LED1, indicating that it is operating. Confirm that your host computer can communicate with the GreatFET One by typing:

greatfet info

This is an example of a command-line tool that is accessible as a subcommand of the unified “greatfet” command. The “greatfet” command is also installed as “gf”. Let’s try the abbreviated form:

gf info

The output of this command shows you information about connected GreatFET devices.

Update Firmware

After installing or updating GreatFET software on your host computer it is important to update the firmware on your GreatFET One to match. This can be done with a single command:

gf fw --auto

Blinking an LED

There are four fabulous LEDs on GreatFET One. LED1 normally indicates a heartbeat, but you can do whatever you like with LED2, LED3, and LED4. Let’s try blinking an LED from Python.

First start up an interactive Python shell:

gf shell

The “gf shell” command starts an IPython shell, connects to the first GreatFET One it finds, and sets up an object called “gf” that you can use to interact with the GreatFET One.

Try turning on LED2 from the shell:

led = gf.leds[2]
led.toggle()

now try blinking LED3 a few times:

import time
for i in range(10):
	gf.leds[3].toggle()
	time.sleep(0.2)

That’s it! To get started exploring the Python capabilities of GreatFET, you can try using the tab key to complete commands or try the built-in help:

help(gf.leds[3])

For bonus points, see if you can turn off the heartbeat and control LED1. Here’s a help command to get you started:

help(gf.apis.heartbeat)

When you’re ready to try something new, type “exit” to close the Python shell and check out one of the other tutorials!