.. zephyr:board:: slwrb4180a

Overview
********

The EFR32MG21 Mighty Gecko Radio Board is one of the two
radio boards delivered with `EFR32-SLWSTK6006A Website`_. It contains
a Wireless System-On-Chip from the EFR32MG21 family built on an
ARM Cortex®-M33F processor with excellent low power capabilities.

The BRD4180A a.k.a. SLWRB4180A radio board plugs into the Wireless Starter Kit
Mainboard BRD4001A and is supported as one of :ref:`silabs_radio_boards`.

Hardware
********

- EFR32MG21A020F1024IM32 Mighty Gecko SoC
- CPU core: ARM Cortex®-M33 with FPU
- Flash memory: 1024 kB
- RAM: 96 kB
- Transmit power: up to +20 dBm
- Operation frequency: 2.4 GHz
- Crystals for LFXO (32.768 kHz) and HFXO (38.4 MHz).

For more information about the EFR32MG21 SoC and BRD4180A board, refer to these
documents:

- `EFR32MG21 Website`_
- `EFR32MG21 Datasheet`_
- `EFR32xG21 Reference Manual`_
- `EFR32-SLWSTK6006A Website`_
- `BRD4180A User Guide`_

Supported Features
==================

The board configuration supports the following hardware features:

+-----------+------------+-------------------------------------+
| Interface | Controller | Driver/Component                    |
+===========+============+=====================================+
| MPU       | on-chip    | memory protection unit              |
+-----------+------------+-------------------------------------+
| NVIC      | on-chip    | nested vector interrupt controller  |
+-----------+------------+-------------------------------------+
| SYSTICK   | on-chip    | systick                             |
+-----------+------------+-------------------------------------+
| COUNTER   | on-chip    | rtcc                                |
+-----------+------------+-------------------------------------+
| FLASH     | on-chip    | flash memory                        |
+-----------+------------+-------------------------------------+
| GPIO      | on-chip    | gpio                                |
+-----------+------------+-------------------------------------+
| UART      | on-chip    | serial port-polling;                |
|           |            | serial port-interrupt               |
+-----------+------------+-------------------------------------+
| I2C       | on-chip    | i2c port-polling                    |
+-----------+------------+-------------------------------------+
| DMA       | on-chip     | ldma                               |
+-----------+------------+-------------------------------------+
| WATCHDOG  | on-chip    | watchdog                            |
+-----------+------------+-------------------------------------+

Other hardware features are currently not supported by the port.

Connections and IOs
===================

In the following table, the column **Name** contains Pin names. For example, PA2
means Pin number 2 on PORTA, as used in the board's datasheets and manuals.

+-------+-------------+-------------------------------------+
| Name  | Function    | Usage                               |
+=======+=============+=====================================+
| PB0   | GPIO        | LED0                                |
+-------+-------------+-------------------------------------+
| PB1   | GPIO        | LED1                                |
+-------+-------------+-------------------------------------+
| PD2   | GPIO        | Push Button PB0                     |
+-------+-------------+-------------------------------------+
| PD3   | GPIO        | Push Button PB1                     |
+-------+-------------+-------------------------------------+
| PD4   | GPIO        | Board Controller Enable             |
|       |             | EFM_BC_EN                           |
+-------+-------------+-------------------------------------+
| PA5   | USART1_TX   | UART Console EFM_BC_TX US1_TX       |
+-------+-------------+-------------------------------------+
| PA6   | USART1_RX   | UART Console EFM_BC_RX US1_RX       |
+-------+-------------+-------------------------------------+

The default configuration can be found in
:zephyr_file:`boards/silabs/radio_boards/slwrb4180a/slwrb4180a_defconfig`

System Clock
============

The EFR32MG21 SoC is configured to use the 38.4 MHz external oscillator on the
board.

Serial Port
===========

The EFR32MG21 SoC has three USARTs.
USART0 is connected to the board controller and is used for the console.

Programming and Debugging
*************************

Flashing
========

Connect the BRD4001A board with a mounted BRD4180A radio module to your host
computer using the USB port.

Here is an example for the :zephyr:code-sample:`hello_world` application.

.. zephyr-app-commands::
   :zephyr-app: samples/hello_world
   :board: slwrb4180a
   :goals: flash

Open a serial terminal (minicom, putty, etc.) with the following settings:

- Speed: 115200
- Data: 8 bits
- Parity: None
- Stop bits: 1

Reset the board and you should see the following message in the terminal:

.. code-block:: console

   Hello World! slwrb4180a


.. _EFR32-SLWSTK6006A Website:
   https://www.silabs.com/products/development-tools/wireless/efr32xg21-wireless-starter-kit

.. _BRD4180A User Guide:
   https://www.silabs.com/documents/public/user-guides/ug385-brd4180a-user-guide.pdf

.. _EFR32MG21 Website:
   https://www.silabs.com/products/wireless/mesh-networking/efr32mg21-series-2-socs

.. _EFR32MG21 Datasheet:
   https://www.silabs.com/documents/public/data-sheets/efr32mg21-datasheet.pdf

.. _EFR32xG21 Reference Manual:
   https://www.silabs.com/documents/public/reference-manuals/efr32xg21-rm.pdf