/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/**
 * @defgroup AVR_DRIVERS AVR Drivers
 * @details This section describes all the supported drivers on the AVR
 *          platform and the implementation details of the single drivers.
 *
 * @ingroup platforms
 */

/**
 * @defgroup AVR_HAL AVR Initialization Support
 * @details On the AVR platform the HAL driver is a stub and does not perform
 *          any platform-specific initialization, it still performs the
 *          initialization of the other drivers.
 *
 * @ingroup AVR_DRIVERS
 */

/**
 * @defgroup AVR_PAL AVR PAL Support
 * @details The AVR PAL driver uses the PORT peripherals.
 *
 * @section avr_pal_1 Supported HW resources
 * - PORTA.
 * - PORTB.
 * - PORTC.
 * - PORTD.
 * - PORTE.
 * - PORTF.
 * - PORTG.
 * .
 * @section avr_pal_2 AVR PAL driver implementation features
 * The AVR PAL driver implementation fully supports the following hardware
 * capabilities:
 * - 8 bits wide ports.
 * - Atomic set/reset functions.
 * - Output latched regardless of the pad setting.
 * - Direct read of input pads regardless of the pad setting.
 * .
 * @section avr_pal_3 Supported PAL setup modes
 * The AVR PAL driver supports the following I/O modes:
 * - @p PAL_MODE_RESET.
 * - @p PAL_MODE_UNCONNECTED.
 * - @p PAL_MODE_INPUT.
 * - @p PAL_MODE_INPUT_PULLUP.
 * - @p PAL_MODE_INPUT_ANALOG.
 * - @p PAL_MODE_OUTPUT_PUSHPULL.
 * .
 * Any attempt to setup an invalid mode is ignored.
 *
 * @section avr_pal_4 Suboptimal behavior
 * The AVR PORT is less than optimal in several areas, the limitations
 * should be taken in account while using the PAL driver:
 * - Pad/port toggling operations are not atomic.
 * - Pad/group mode setup is not atomic.
 * - Group set+reset function is not atomic.
 * - Writing on pads/groups/ports programmed as input with pull-up
 *   resistor changes the resistor setting because the output latch is
 *   used for resistor selection.
 * - The PORT registers layout on some devices is not regular (it does
 *   not have contiguous PIN, DDR, PORT registers in this order), such
 *   ports cannot be accessed using the PAL driver. For example, PORT F
 *   on ATmega128. Verify the user manual of your device.
 * .
 * @ingroup AVR_DRIVERS
 */

/**
 * @defgroup AVR_SERIAL AVR Serial Support
 * @details The AVR Serial driver uses the USART peripherals in a
 *          buffered, interrupt driven, implementation.
 *
 * @section avr_serial_1 Supported HW resources
 * The serial driver can support any of the following hardware resources:
 * - USART0.
 * - USART1.
 * .
 * @section avr_serial_2 AVR Serial driver implementation features
 * - Each USART can be independently enabled and programmed.
 * - Fully interrupt driven.
 * .
 * @ingroup AVR_DRIVERS
 */