ChibiOS/ports/ARM7-LPC214x/pal_lld.h

/*
    ChibiOS/RT - Copyright (C) 2006-2007 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/>.
*/

/**
 * @file ports/ARM7-LPC214x/pal_lld.h
 * @brief LPC214x FIO low level driver
 * @addtogroup LPC214x_PAL
 * @{
 */

#ifndef _PAL_LLD_H_
#define _PAL_LLD_H_

#ifndef _LPC214X_H_
#include "lpc214x.h"
#endif

/*===========================================================================*/
/* I/O Ports Types and constants.                                            */
/*===========================================================================*/

/**
 * @brief Width, in bits, of an I/O port.
 */
#define PAL_IOPORTS_WIDTH 32

/**
 * @brief Digital I/O port sized unsigned type.
 */
typedef uint32_t ioportmask_t;

/**
 * @brief Port Identifier.
 */
typedef FIO * ioportid_t;

/*===========================================================================*/
/* I/O Ports Identifiers.                                                    */
/*===========================================================================*/

/**
 * @brief FIO port 0 identifier.
 */
#define IOPORT_A        FIO0Base

/**
 * @brief FIO port 1 identifier.
 */
#define IOPORT_B        FIO1Base

/*===========================================================================*/
/* Implementation, some of the following macros could be implemented as      */
/* functions, please put them in a file named ioports_lld.c if so.           */
/*===========================================================================*/

/**
 * @brief FIO subsystem initialization.
 * @details Enables the access through the fast registers.
 */
#define pal_lld_init() {                                                \
  SCS = 3;                                                              \
}

/**
 * @brief Reads an I/O port.
 * @details This function is implemented by reading the FIO PIN register, the
 *          implementation has no side effects.
 *
 * @param[in] port the port identifier
 * @return the port bits
 *
 * @note This function is not meant to be invoked directly by the application
 *       code.
 */
#define pal_lld_readport(port) ((port)->FIO_PIN)

/**
 * @brief Reads the output latch.
 * @details This function is implemented by reading the FIO SET register, the
 *          implementation has no side effects.
 *
 * @param[in] port the port identifier
 * @return The latched logical states.
 *
 * @note This function is not meant to be invoked directly by the application
 *       code.
 */
#define pal_lld_readlatch(port) ((port)->FIO_SET)

/**
 * @brief Writes a bits mask on a I/O port.
 * @details This function is implemented by writing the FIO PIN register, the
 *          implementation has no side effects.
 *
 * @param[in] port the port identifier
 * @param[in] bits the bits to be written on the specified port
 *
 * @note This function is not meant to be invoked directly by the application
 *       code.
 */
#define pal_lld_writeport(port, bits) ((port)->FIO_PIN = (bits))

/**
 * @brief Sets a bits mask on a I/O port.
 * @details This function is implemented by writing the FIO SET register, the
 *          implementation has no side effects.
 *
 * @param[in] port the port identifier
 * @param[in] bits the bits to be ORed on the specified port
 *
 * @note This function is not meant to be invoked directly by the application
 *       code.
 */
#define pal_lld_setport(port, bits) ((port)->FIO_SET = (bits))

/**
 * @brief Clears a bits mask on a I/O port.
 * @details This function is implemented by writing the FIO CLR register, the
 *          implementation has no side effects.
 *
 * @param[in] port the port identifier
 * @param[in] bits the bits to be cleared on the specified port
 *
 * @note This function is not meant to be invoked directly by the application
 *       code.
 */
#define pal_lld_clearport(port, bits) ((port)->FIO_CLR = (bits))

/**
 * @brief Writes a value on an I/O bus.
 * @details This function is implemented by writing the FIO PIN and MASK
 *          registers, the implementation is not atomic because the multiple
 *          accesses.
 *
 * @param[in] port the port identifier
 * @param[in] mask the group mask
 * @param[in] offset the group bit offset within the port
 * @param[in] bits the bits to be written. Values exceeding the group width
 *            are masked.
 *
 * @note This function is not meant to be invoked directly by the application
 *       code.
 */
#define pal_lld_writegroup(port, mask, offset, bits) {                  \
  (port)->FIO_MASK = (mask) << (offset);                                \
  (port)->FIO_PIN = (bits) << (offset);                                 \
  (port)->FIO_MASK = 0;                                                 \
}

/**
 * @brief Writes a logical state on an output pad.
 *
 * @param[in] port the port identifier
 * @param[in] pad the pad number within the port
 * @param[out] bit the logical value, the value must be @p 0 or @p 1
 *
 * @note This function is not meant to be invoked directly by the application
 *       code.
 */
#define pal_lld_writepad(port, pad, bit) pal_lld_writegroup(port, 1, pad, bit)

/**
 * @brief FIO port setup.
 * @details This function initializes a FIO port, note that this functionality
 *          is LPC214x specific and non portable.
 */
#define pal_lld_lpc214x_set_direction(port, dir) {                      \
  (port)->FIO_DIR = (dir);                                              \
}

#endif /* _PAL_LLD_H_ */

/** @} */