Add updated linux instructions

Author: karlsoderby

Diff for: content/hardware/02.hero/boards/uno-wifi-rev2/tutorials/uno-wifi-rev-2/uno-wifi-r2-chromebook-installation/uno-wifi-r2-chromebook-installation.md

@@ -18,7 +18,7 @@ software:
 
 The [UNO WiFi Rev 2](https://store.arduino.cc/arduino-uno-wifi-rev2) is the connected version of the classic UNO board. If you are using a **Chromebook**, setting up your board is a bit different for this particular board:
 
-- You will need to upgrade the firmware using either a **Windows/Mac** computer, prior to programming it via a Chromebook. Detailed instructions are provided in this tutorial, and the process only takes a few minutes!
+- You will need to upgrade the firmware using either a **Windows/Mac/Linux** computer, prior to programming it via a Chromebook. Detailed instructions are provided in this tutorial, and the process only takes a few minutes!
 - It is only possible to use the [Web Editor](https://create.arduino.cc/editor), an online IDE that is part of the [Arduino Cloud](https://cloud.arduino.cc/).
 
 ***Note that only the Web Editor is supported in Chromebooks. It is not possible to configure and upload to UNO WiFi Rev 2 boards via the [IoT Cloud](https://create.arduino.cc/iot/things).***
@@ -42,23 +42,23 @@ The goals of this project are:
 
 ## Upgrading Firmware
 
-Since Chromebooks cannot run executables, the firmware upgrade for the UNO WiFi Rev 2 needs to be done through a computer with the Windows/Mac OS installed. 
+Since Chromebooks cannot run executables, the firmware upgrade for the UNO WiFi Rev 2 needs to be done through a Windows/Mac/Linux computer. 
 
 **1.** Make sure you have installed [Arduino IDE 1.8.X](https://www.arduino.cc/en/software).
 
 **2.** Download the [optiboot_atmega4.hex](/resources/firmware/optiboot_atmega4809.hex) file, and move it to your **Desktop folder**. 
 
 ![.hex file in your Desktop folder.](assets/hex-file-desktop.png)
 
-**3.** Open your Command Prompt (Windows) or Terminal (Mac), copy paste the command for your OS from the snippets below.
+**3.** Open your Command Prompt (Windows) or Terminal (Mac/Linux), copy paste the command for your OS from the snippets below.
 
-### Mac Command
+### Mac
 
 ```
 /Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avrdude -C /Applications/Arduino.app/Contents/Java/hardware/tools/avr/etc/avrdude.conf -v -patmega4809 -cxplainedmini_updi -Pusb -b115200 -e -D -Ufuse2:w:0x01:m -Ufuse5:w:0xC9:m -Ufuse8:w:0x02:m -Uflash:w:/Users/$(whoami)/Desktop/optiboot_atmega4809.hex:i
 ```
 
-### Windows Command
+### Windows
 
 ```
 "C:/Program Files (x86)/Arduino/hardware/tools/avr/bin/avrdude.exe" -C "C:/Program Files (x86)/Arduino/hardware/tools/avr/etc/avrdude.conf" -v -patmega4809 -cxplainedmini_updi -Pusb -b115200 -e -D -Ufuse2:w:0x01:m -Ufuse5:w:0xC9:m -Ufuse8:w:0x02:m -Uflash:w:%userprofile%\Desktop\optiboot_atmega4809.hex:i
@@ -70,6 +70,22 @@ Since Chromebooks cannot run executables, the firmware upgrade for the UNO WiFi
 
 **5.** Now that your firmware is upgraded, you should see your board blinking (1 second off, followed by a quick blink). This is another proof that it was successful. You can now disconnect your board, and **plug it into your Chromebook.** 
 
+## Linux
+
+In the terminal, navigate to your root directory.
+
+```
+cd /
+```
+
+Then, run the following command:
+
+```
+home/$(whoami)/Downloads/arduino-1.8.19-linux64/arduino-1.8.19/hardware/tools/avr/bin/avrdude -C home/$(whoami)/Downloads/arduino-1.8.19-linux64/arduino-1.8.19/hardware/tools/avr/etc/avrdude.conf -v -patmega4809 -cxplainedmini_updi -Pusb -b115200 -e -D -Ufuse2:w:0x01:m -Ufuse5:w:0xC9:m -Ufuse8:w:0x02:m  -Uflash:w:/home/$(whoami)/Desktop/optiboot_atmega4809.hex:i
+```
+
+***Please note that on Linux, the path to the AVRDUDE tool may vary.***
+
 ### Check AVRDUDE Installation
 
 The above commands utilizes a tool called **AVRDUDE**, which is included in each version of the IDE. To check whether it is accessible on your computer, you can run the following commands. 
@@ -86,12 +102,18 @@ The above commands utilizes a tool called **AVRDUDE**, which is included in each
 /Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avrdude
 ```
 
+**Linux:**
+
+```
+/home/$(whoami)/Downloads/arduino-1.8.19-linux64/arduino-1.8.19/hardware/tools/avr/bin/avrdude
+```
+
 ### Troubleshoot
 
 If the command fails to upgrade the firmware, please make sure that:
 
 - Arduino IDE / AVRDUDE is installed.
-- That you are using a Windows/Mac machine (remember, this cannot be performed on a Chromebook).
+- That you are using a Windows/Mac/Linux computer (remember, this cannot be performed on a Chromebook).
 - That you have the `.hex` file in the Desktop folder. The command is written to look for it in that specific folder, so if it is not present, it will not work.
 
 ## Install Arduino App (Chrome Store)