/**
@defgroup    boards_weact-f411ce WeAct-F411CE board
@ingroup     boards
@brief       Support for the WeAct-F411CE Board

## Overview

WeAct-F411CE is a board with the same form-factor as the blue/blackpill,
but with an STM32F411CEU6 and a USB-C connector.

It is available on sites like AliExpress for less than 4€.

## Hardware

![WeAct-F411CE](https://user-images.githubusercontent.com/1301112/69389644-eb5fb080-0ccc-11ea-8002-67d3db851250.png)

### MCU
| MCU              | STM32F411CE           |
|:---------------- |:--------------------- |
| Family           | ARM Cortex-M4F        |
| Vendor           | ST Microelectronics   |
| RAM              | 128KiB                |
| Flash            | 512KiB                |
| Frequency        | up to 100MHz          |
| FPU              | yes                   |
| Timers           | 8 (2x watchdog, 1 SysTick, 6x 16-bit)    |
| ADCs             | 1x 12-bit             |
| UARTs            | 3                     |
| SPIs             | 5                     |
| I2Cs             | 3                     |
| RTC              | 1                     |
| Vcc              | 2.0V - 3.6V           |
| Datasheet        | [Datasheet](https://www.st.com/resource/en/datasheet/stm32f411ce.pdf) |
| Reference Manual | [Reference Manual](https://www.st.com/content/ccc/resource/technical/document/reference_manual/9b/53/39/1c/f7/01/4a/79/DM00119316.pdf/files/DM00119316.pdf/jcr:content/translations/en.DM00119316.pdf) |

## Flashing the device
The device comes with a bootloader that allows flashing via `dfu-util`.

There are two buttons on the board labeled `BOOT0` and `NRST`.

 - Press and hold down `NRST` to reset the CPU
 - Press `BOOT0` while keeping `NRST` held down
 - Release `NRST`, afterwards release `BOOT0`

The board will now show up as `0483:df11` - `STM32 BOOTLOADER` and will accept
firmware using the DFU protocol.

You can upload your RIOT-firmware by typing

```
make BOARD=weact-f411ce flash
```

*Note:* You need to have write permissions to the device.
On Linux you could add yourself to the `plugdev` group and store the following as `/etc/udev/rules.d/99-weact-f411ce.rules`:

```
SUBSYSTEMS=="usb", ATTRS{idVendor}=="0483", ATTRS{idProduct}=="df11", GROUP="plugdev", MODE="660"
```

## UART

stdio is provided through USB CDC ACM so the board can be used
without any extra hardware, save for a USB-C cable.

 */