Getting started with Meshcore¶

There are two ways of configuring a Meshcore device:

a companion: this a "client" to the mesh, that needs a repeater to relay messages, but that is the primary interface to send and receive messages
a repeater: this is the "relay" in the mesh, which transmits messages between clients and repeaters and other clients and repeaters

If you're just getting started, try a Companion, and we'll assume you're configuring a Companion for the rest of this guide, unless otherwise noted.

Warning

Some Meshcore configurations exposes your location by default on devices which have a GPS device! To work around this problem, you can disable the GPS or reduce the coordinates precision, we recommend two digits (~1km) for clients and 3 digits (~100m) for repeaters.

Hardware¶

Pick a device in our hardware review notes or the official hardware list.

It's cheap! Expect to pay 50$CAD for a starter kit, 150$CAD for a decent solar relay.

Tip

If the device you picked comes with a removable antenna, make sure you connect the antenna before powering up the device. A radio that transmits without an antenna can damage itself!

Software¶

Now you own a LoRa transceiver, congratulations! The next step is to make sure it runs Meshcore by installing firmware on it, and that you can talk to the device, typically by installing an app on your phone.

Flash the firmware on the device¶

First you need to flash your device, which essentially means connecting to the following website from a Chrome (or derivative) web browser:

https://meshcore.co.uk/flasher.html

You may skip this step if it comes flashed with Meshcore already.

Important

This is the moment when you pick between Companion and Repeater, and you can't go back without reflashing!

Tip

If you are configuring a repeater, this is also the step where you configure the repeater through the web interface. Some settings can be performed over Bluetooth later.

You need to at least:

set a name to the router: the local convention is to use a YUL- prefix and the general location of the router, e.g. YUL-Villeray or YUL-Parc-Extension
set an admin password and save it to your password manager for remote administration

The remaining settings can be done over Bluetooth from a companion, which we'll assume below.

Tip

Many settings can be done over a serial port, if you're an advanced user. You can connect to the serial port on Linux with tio:

tio /dev/ttyUSB0

Then the above commands are:

set name YUL-Villeray

You can also connect to your devices with the meschore-cli program. The full command line reference is available in the upstream documentation.

Install an app¶

Unless you picked a standalone device, now you'll need something to talk with people on the mesh. Unless you use a standalone device, this means installing software on your phone.

You can try that from your computer with a web browser by using one of the web-based apps: Liam Cottle's and MeshOS. There are also iOS and Android versions.

A warning about proprietary software

Both official Meshcore apps are proprietary software that do not publish their source code and require a subscription or a 10 second wait time for certain features.

You can work around some of those problems by installin the open app which requires going through Obtainium on Android or test flight. It's a little complicated, so don't venture there unless you get frustrated with the official apps (and, honestly, you might!).

Backing up Meshtastic before flashing

If you're replacing a Meshtastic device, you can backup your Meshtastic configuration and keys to restore those if you change your mind or want to use that configuration on another device. This can be done by exporting the configuration in the Meshtastic app settings, or with the Meshtastic command line tool:

meshtastic --export-config > devicename.yaml

Configuration¶

The main configuration you need to do on the device is set the "region".

The Montreal mesh uses the "recommended USA / Canada" preset:

Frequency: 910.525 MHz
Bandwidth: 62.5 kHz
Spreading Factor (SF): 7 or SF7
Coding Rate (CR): 5 or CR5

You shouldn't need to write those down by hands, generally. Just pick the recommended preset.

Tip

You can also perform this configuration over the command line:

set freq 910.525
set bw 62.5
set sf 7
set cr 5

You made it! Say hi!

At this point, your companion should be properly configured. Repeaters require a little more work, below.

Introduce yourself! Say "hi!" on the "Public" channel. Explain what device did you setup, where's your general area, what's the weather like, etc. Be kind, reply to people, participate!

Multi-byte repeater configuration

On a repeater, you should also configure the router identifier for multi-byte path routing, specifically for three bytes, which is called "mode 2". For this, you need to enter the "command line" mode and enter the command:

set path.hash.mode 2

You can confirm the current mode with:

get path.hash.mode

And some relays require a reboot for the change to take effect:

reboot

Others have reported having to do the change twice for it to take effect as well.

Repeaters can lose track of time

Repeaters can lose their time after reboot.

Make sure the repeater has an accurate clock. Companion apps can be configured to automatically sync the clock on login to workaround this issue.

Repeaters without an accurate clock route packets properly, but its adverts will be ignored until its time is accurate.

Channels¶

If you want to go a little further, you should know that Meshcore supports the concept of "channels" which are essentially different communities separated by their own private keys.

Many of those are "public", in the sense that the encryption key is derived from an easy to guess name, like #testing, so those are not "really" encrypted.

But you can use channels to really create your own secret communication channels. Contents will be encrypted as long as the channel name remains secret, but who is talking to who, the number of messages sent will be visible to an attacker.

Public channels¶

We know about the follow channels currently in use:

Name	Hex Key	Base64	Purpose
Public	`8b3387e9c5cdea6ac9e5edbaa115cd72`	`izOH6cXN6mrJ5e26oRXNcg==`	General conversations
`#testing`	`cde5e82cf515647dcb547a79a4f065d1`	`zeXoLPUVZH3LVHp5pPBl0Q==`	Should be used for test
`#wardriving`	`e3c26491e9cd321e3a6be50d57d54acf`	`48JkkenNMh46a+UNV9VKzw==`	Used by Meshmapper pings

You should generally not need the hex and Base64 keys. They are only provided here as a reference for some rate situations where you need to enter the secret key directly. (For example, some standalone firmware like the T-Deck require this.)

See also the channels used in other communities: