Prerequisites

What you need

A Linux based machine that has a Bluetooth HCI interface

In this tutorial we are going to use a Raspberry Pi 4 running Ubuntu 20.04 for Raspberry

IMPORTANT NOTE : It is actually MANDATORY to use Ubuntu Server 64bits 20.04 LTS3 (arm64) if implementing Matter support on Raspberry Pi

Any other distro, including Raspbian will not allow you to build required Matter tools

Still this could be achieved on any other Ubuntu 20.04 system that has a BLE interface
Enable ssh on your Raspberry Pi (Optional, only if you do not use the RPi's HDMI interface)

You can find a nice guide on how to achieve this according to your RPi usage on this PhoenixNAP Knowledge Base Article

You will also need an SSH client if you are connecting remotely to the Raspberry Pi or Build computer :
- PuTTY
- A good old Linux terminal (For Windows users, WSL can achieve this)
A Silicon Labs Wireless Starter Kit which can support Thread developement

Full list is available on this page

Preferred and most economic option being our Thunderboard Sense 2
git installed on your build machine

For above mentionned systems a simple package manager installation should work
```
sudo apt install git
```
A Jlink Flash Utility installed on your machine

This guide will use the JLink Package for Linux

But other options such as Simplicity Commander or Simplicity Studio Flash Programmer would also work

Note :

This guide does not cover how to get a Raspberry pi up and running. For that please refer to this guide

This guide does not cover how to perform a Linux installation on a computer. For this please refer to this guide

Getting started

Flash your raspberry pi SD Card using Raspberry Pi Imager (For Raspberry Pi users only)

Remeber, do not flash the regular Raspberry Pi OS but Ubuntu Server 64bits 20.04 LTS3 (arm64) image

Default login and password are : ubuntu ubuntu

You will be asked to change it upon first login
Get the IP address of your Raspberry Pi (For SSH users only)

There are a few options here :
- Use your router's management interface
- You can use a network discovery tool such as Angry IP Scanner (Win, Mac, Linux)
  
  A portable (no install required) executable is provided for Windows users
  
  Just scan your subnet for open ssh ports if you do not have a lot of devices supporting it (port 22)
Open a terminal on your Raspberry Pi (either local or via ssh from one of the above mentioned options) :

For example using Linux/WSL ssh terminal command :
```
ssh ubuntu@192.168.1.18
```
cd to your home directory if not already there :
```
cd ~/
```
Create a dedicated folder within your /home/ directory for this development purpose
```
mkdir ~/border_router_dev
cd ~/border_router_dev
```
Check that you have git installed
```
sudo apt update
sudo apt install git
sudo apt update
```
If some packages can be upgraded feel free to do so, but ensure to run an apt update as last command
Make sure you have JLink Utilities installed

Go to JLink Download Page Look for the package that suits your platform and Download it

For ease of use in a command line environment, we hosted a few packages on a Dropbox:
For a raspberry pi setup running Ubuntu OS 64bit, downloaod as follows:
```
wget https://www.dropbox.com/s/yq7ncfc5y20b3hw/JLink_Linux_V758c_arm64.deb
```
Then install using :
```
sudo apt update
sudo apt install ./JLink_Linux_V758c_arm64.deb
sudo apt update
```

Plug in your Thunderboard Sense 2 to your Raspberry Pi and check it is enumerated

ls -ail /dev/ttyACM* 
450 crw-rw-rw- 1 root dialout 166, 0 Nov 29 19:14 /dev/ttyACM0
  

Check that you can erase the Thunderboard Sense 2 using JLinkExe utility

First launch the JLinkExe utility using JLinkExe -device EFR32MG12P432F1024GL125 -speed 4000 -if SWD -autoconnect 1:

JLinkExe -device EFR32MG12P432F1024GL125 -speed 4000 -if SWD -autoconnect 1

SEGGER J-Link Commander V7.58c (Compiled Nov 24 2021 17:29:09)
DLL version V7.58c, compiled Nov 24 2021 17:28:52

Connecting to J-Link via USB...O.K.
Firmware: Silicon Labs J-Link OB compiled Oct  3 2017 10:31:49
Hardware version: V1.00
S/N: 440162855
License(s): RDI, FlashBP
VTref=3.233V
Device "EFR32MG12PXXXF1024" selected.


Connecting to target via SWD
InitTarget() start
InitTarget() end
Found SW-DP with ID 0x2BA01477
DPv0 detected
CoreSight SoC-400 or earlier
Scanning AP map to find all available APs
AP[1]: Stopped AP scan as end of AP map has been reached
AP[0]: AHB-AP (IDR: 0x24770011)
Iterating through AP map to find AHB-AP to use
AP[0]: Core found
AP[0]: AHB-AP ROM base: 0xE00FF000
CPUID register: 0x410FC241. Implementer code: 0x41 (ARM)
Found Cortex-M4 r0p1, Little endian.
FPUnit: 6 code (BP) slots and 2 literal slots
CoreSight components:
ROMTbl[0] @ E00FF000
[0][0]: E000E000 CID B105E00D PID 000BB00C SCS-M7
[0][1]: E0001000 CID B105E00D PID 003BB002 DWT
[0][2]: E0002000 CID B105E00D PID 002BB003 FPB
[0][3]: E0000000 CID B105E00D PID 003BB001 ITM
[0][4]: E0040000 CID B105900D PID 003BB923 TPIU-Lite
[0][5]: E0041000 CID B105900D PID 000BB925 ETM
Cortex-M4 identified.
J-Link>

  

This will open a prompt in which you can issue flash commands to the device

Then simply type erase

J-Link>erase
Without any given address range, Erase Chip will be executed
Erasing device...
Unable to load library icui18n "Cannot load library icui18n: (icui18n: cannot open shared object file: No such file or directory)"
JLinkGUIServerExe: cannot connect to X server
J-Link: Flash download: Total time needed: 0.218s (Prepare: 0.156s, Compare: 0.000s, Erase: 0.053s, Program: 0.000s, Verify: 0.000s, Restore: 0.008s)
J-Link: Flash download: Total time needed: 0.111s (Prepare: 0.075s, Compare: 0.000s, Erase: 0.027s, Program: 0.000s, Verify: 0.000s, Restore: 0.008s)
J-Link: Flash download: Total time needed: 0.111s (Prepare: 0.075s, Compare: 0.000s, Erase: 0.027s, Program: 0.000s, Verify: 0.000s, Restore: 0.008s)
J-Link: Flash download: Total time needed: 0.576s (Prepare: 0.075s, Compare: 0.000s, Erase: 0.489s, Program: 0.000s, Verify: 0.000s, Restore: 0.011s)
Erasing done.
J-Link>
  

Finally just leave the prompt by typing q

J-Link>q
pi@raspberrypi:~/border_router_dev
  

A dedicated KBA has been writen in our community for alternative help using the JLinkExe utility

Update your Thunderboard Sense 2 Kit firmware with one that disbales UART HW Flow control

First verify your firmware version is later than 1v3p0

Otherwise you could face Border Router runtime errors such as RadioSpinelNoResponse

To do so use one of the 2 options below

At the time of writing (11/29/2021) there are two ways to update your Starter Kit's firmware

Both CANNOT be run on Raspberry Pi, only on Windows, Mac and Linux x86_64 platforms
- Using Simplicity Commander Start by downloading the utility for your computer: Installer for Linux Installer for Windows Installer for Mac
  
  Note that Commander is installed by Simplicity Studio in <StudioInstallDir>\SimplicityStudio\v5\developer\adapter_packs\commander
  
  Or install each package and dependencies according to their README
  
  Download the latest firmware image from here
  
  If already downloaded by Simplicity Studio, it can also be found in : <StudioInstallDir>\SimplicityStudio\v5\offline\hwtools\firmware\S1015C_adapter_firmware_package Within linux use wget :
```
wget https://www.dropbox.com/s/rlik7d0ktvuqv8h/S1015C_adapter_firmware_package_1v4p2b352.emz
```
  Commander can be used either by command line or GUI, the easiest being the GUI
  
  GUI Verify and Install :
  
  Command line Verify and Install :
  
  The command documented in UG162 Chapter 6.8.1 is
  
  $ commander adapter fwupgrade --serialno <J-Link serial number> <filename>
  
  To find your JLink serial number you can use JLinkExe :
```
JLinkExe
SEGGER J-Link Commander V7.58c (Compiled Nov 24 2021 17:29:09)
DLL version V7.58c, compiled Nov 24 2021 17:28:52

Connecting to J-Link via USB...O.K.
Firmware: Silicon Labs J-Link OB compiled Jun  6 2019 18:14:01
Hardware version: V1.00
S/N: 440162855
License(s): RDI, FlashBP
VTref=3.223V

Type "connect" to establish a target connection, '?' for help
J-Link>q
```
  In our case : $ commander adapter fwupgrade --serialno 440162855 S1015C_adapter_firmware_package_1v4p2b352.emz
  
  Note : As mentioned above, this does not apply to Raspberry Pi OS
- Using Simplicity Studio Plug in your Thunderboard to the computer
  
  And open Simplicity's Launcher Perspective :
Redo 8. and 9. to ensure you still have your Thunderboard Sense 2 connected and writeable

Troubleshoot

If you precisely follow all of the previous steps, you should have a ready to use Linux envirnment

Still, if you run into some of these issues:

apt operations fails because of E: Could not get lock /var/lib/dpkg/lock

Follow method 2 of this knowledge article
ssh login fails due to existing known_host

This is due to the fact that you already had connected using ssh to the host but might have flashed a new linux distro on it

As per sshshell feedback, use ssh-keygen -f "/home/brian/.ssh/known_hosts" -R "<your_target_ip>"