@@ -11,10 +11,8 @@ When you run [`arduino-cli board list`][arduino cli board list], your board does

FQBN stands for Fully Qualified Board Name. It has the following format:

`VENDOR:ARCHITECTURE:BOARD_ID[:MENU_ID=OPTION_ID[,MENU2_ID=OPTION_ID ...]]`, with each `MENU_ID=OPTION_ID` being an

optional key-value pair configuration. Each field accepts letters (`A-Z` or `a-z`), numbers (`0-9`), underscores (`_`),

dashes(`-`) and dots(`.`). The special character `=` is accepted in the configuration value. The `VENDOR` and

`ARCHITECTURE` parts can be empty. For a deeper understanding of how FQBN works, you should understand the [Arduino

platform specification][0].

optional key-value pair configuration. The `VENDOR` and `ARCHITECTURE` parts can be empty. For a deeper understanding of

how FQBN works, you should understand the [Arduino platform specification][0].

## How to set multiple board options?

@@ -64,6 +64,8 @@ The metadata fields are:

- `name`: the folder used for the installed cores. The

[vendor folder](platform-specification.md#hardware-folders-structure) name of the installed package is determined by

this field

- The value must not contain any characters other than the letters `A`-`Z` and `a`-`z`, numbers (`0`-`9`), underscores

(`_`), dashes (`-`), and dots (`.`).

- `maintainer`: the extended name of the vendor that is displayed on the Arduino IDE Boards Manager GUI

- `websiteURL`: the URL to the vendor's website, appears on the Arduino IDE Boards Manager as a "More info" link

- `email`: the email of the vendor/maintainer

@@ -260,6 +262,8 @@ Each PLATFORM describes a core for a specific architecture. The fields needed ar

- `name`: the extended name of the platform that is displayed on the Boards Manager GUI

- `architecture`: is the architecture of the platform (avr, sam, etc...). It must match the architecture of the core as

explained in the [Arduino platform specification](platform-specification.md#hardware-folders-structure)

- The value must not contain any characters other than the letters `A`-`Z` and `a`-`z`, numbers (`0`-`9`), underscores

(`_`), dashes (`-`), and dots (`.`).

- `version`: the version of the platform.

- `deprecated`: (optional) setting to `true` causes the platform to be moved to the bottom of all Boards Manager and

[`arduino-cli core`](https://arduino.github.io/arduino-cli/latest/commands/arduino-cli_core/) listings and marked

@@ -24,7 +24,11 @@ Alternatively, a platform may be manually installed by the user inside the Sketc

- `{directories.user}` is the user directory as specified in the

[configuration file](configuration.md#default-directories).

- `{VENDOR_NAME}` is the identifier of the vendor/maintainer of the platform.

- The name of the vendor directory must not contain any characters other than the letters `A`-`Z` and `a`-`z`, numbers

(`0`-`9`), underscores (`_`), dashes (`-`), and dots (`.`).

- `{ARCHITECTURE}` is the architecture of the CPU used in the platform.

- The name of the architecture directory must not contain any characters other than the letters `A`-`Z` and `a`-`z`,

numbers (`0`-`9`), underscores (`_`), dashes (`-`), and dots (`.`).

A vendor/maintainer may have multiple supported architectures.

@@ -534,6 +538,9 @@ This file contains definitions and metadata for the boards supported by the plat

short name, the board ID. The settings for a board are defined through a set of properties with keys having the board ID

as prefix.

The board ID must not contain any characters other than the letters `A`-`Z` and `a`-`z`, numbers (`0`-`9`), underscores

(`_`), and dashes (`-`).

For example, the board ID chosen for the Arduino Uno board is "uno". An extract of the Uno board configuration in

boards.txt looks like:

@@ -1591,8 +1598,13 @@ This board was produced in two models, one with an ATmega168 microcontroller and

going then to define a custom option, using the "cpu" MENU_ID, that allows the user to choose between the two different

microcontrollers.

We must first define a set of **menu.MENU_ID=Text** properties. **Text** is what is displayed on the GUI for every

custom menu we are going to create and must be declared at the beginning of the boards.txt file:

We must first define a set of **menu.MENU_ID=Text** properties.

The menu ID must not contain any characters other than the letters `A`-`Z` and `a`-`z`, numbers (`0`-`9`), underscores

(`_`), and dashes (`-`).

**Text** is what is displayed on the GUI for every custom menu we are going to create and must be declared at the

beginning of the boards.txt file:

```

menu.cpu=Processor

@@ -1627,7 +1639,12 @@ duemilanove.menu.cpu.atmega168=ATmega168

We have defined two values: "atmega328" and "atmega168".<br> Note that the property keys must follow the format

**BOARD_ID.menu.MENU_ID.OPTION_ID=Text**, where **Text** is what is displayed under the "Processor" menu in the IDE's

GUI.<br> Finally, the specific configuration for each option value:

GUI.

The option ID must not contain any characters other than the letters `A`-`Z` and `a`-`z`, numbers (`0`-`9`), underscores

(`_`), dashes (`-`), and equal signs (`=`).

Finally, the specific configuration for each option value:

```

[.....]