/**
 * @defgroup    boards_teensy31 Teensy3.1 & 3.2
 * @ingroup     boards
 * @brief       Support for the Teensy3.1 & 3.2
 *
 * ### General information
 *
 * Teensy3.1 & 3.2 boards are development boards made by
 * [PJRC](https://www.pjrc.com/teensy/teensy31.html).
 *
 * Teensy3.1 & 3.2 boards are built based on the Freescale MK20DX256VLH7
 * microcontroller. See [Datasheet](http://cache.freescale.com/files/32bit/doc/data_sheet/K20P64M72SF1.pdf).
 *
 * ### Pinout
 *
 * <img src="https://www.pjrc.com/teensy/teensy32_front_pinout.png"
 *      alt="Teensy 3.2 front pinout" style="width:800px;"/>
 *
 * <img src="https://www.pjrc.com/teensy/teensy32_back_pinout.png"
 *      alt="Teensy 3.2 back pinout" style="width:800px;"/>
 *
 * ### Flash the board
 *
 * 1. Put the board in bootloader mode by tapping the reset button.<br/>
 *    The board should remain in bootloader mode until flashed.
 *
 * 2. Use `BOARD=teensy31` with the `make` command. This works for Teensy 3.1 & 3.2<br/>
 *    Example with `hello-world` application:
 * ```
 *      make BOARD=teensy31 -C examples/hello-world flash
 * ```
 *
 * ### Accessing STDIO via UART
 *
 * To access the STDIO of RIOT, a FTDI to USB converter needs to be plugged to
 * the RX/TX pins on the board (pins 0 and 1 of the board).
 */