File content as of revision 0:1063a091a062:

/**
 * @file    : lpc17xx_wdt.c
 * @brief    : Contains all functions support for WDT firmware library on LPC17xx
 * @version    : 1.0
 * @date    : 9. April. 2009
 * @author    : HieuNguyen
 **************************************************************************
 * Software that is described herein is for illustrative purposes only
 * which provides customers with programming information regarding the
 * products. This software is supplied "AS IS" without any warranties.
 * NXP Semiconductors assumes no responsibility or liability for the
 * use of the software, conveys no license or title under any patent,
 * copyright, or mask work right to the product. NXP Semiconductors
 * reserves the right to make changes in the software without
 * notification. NXP Semiconductors also make no representation or
 * warranty that such application will be suitable for the specified
 * use without further testing or modification.
 **********************************************************************/

/* Peripheral group ----------------------------------------------------------- */
/** @addtogroup WDT
 * @{
 */

/* Includes ------------------------------------------------------------------- */
#include "lpc17xx_wdt.h"
#include "lpc17xx_clkpwr.h"
#include "lpc17xx_pinsel.h"


/* If this source file built with example, the LPC17xx FW library configuration
 * file in each example directory ("lpc17xx_libcfg.h") must be included,
 * otherwise the default FW library configuration file must be included instead
 */
#ifdef __BUILD_WITH_EXAMPLE__
#include "lpc17xx_libcfg.h"
#else
#include "lpc17xx_libcfg_default.h"
#endif /* __BUILD_WITH_EXAMPLE__ */


#ifdef _WDT

/* Private Functions ---------------------------------------------------------- */
/** @defgroup WDT_Private_Functions
 * @{
 */

/********************************************************************//**
 * @brief         Set WDT time out value and WDT mode
 * @param[in]    clk_source select Clock source for WDT device
 * @param[in]    timeout value of time-out for WDT (us)
 * @return        None
 *********************************************************************/
uint8_t WDT_SetTimeOut (uint8_t clk_source, uint32_t timeout)
{

    uint32_t pclk_wdt = 0;
    uint32_t tempval = 0;

    switch ((WDT_CLK_OPT) clk_source)
    {
    case WDT_CLKSRC_IRC:
        pclk_wdt = 4000000;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));
        // Check if it valid
        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            LPC_WDT->WDTC = tempval;
            return    SUCCESS;
        }

        break;

    case WDT_CLKSRC_PCLK:

        // Get WDT clock with CCLK divider = 4
        pclk_wdt = SystemCoreClock / 4;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));

        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_4);
            LPC_WDT->WDTC = (uint32_t) tempval;
            return SUCCESS;
        }

        // Get WDT clock with CCLK divider = 2
        pclk_wdt = SystemCoreClock / 2;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));

        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_2);
            LPC_WDT->WDTC = (uint32_t) tempval;
            return    SUCCESS;
        }

        // Get WDT clock with CCLK divider = 1
        pclk_wdt = SystemCoreClock;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));

        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_1);
            LPC_WDT->WDTC = (uint32_t) tempval;
            return    SUCCESS;
        }
        break ;


    case WDT_CLKSRC_RTC:
        pclk_wdt = 32768;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));
        // Check if it valid
        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            LPC_WDT->WDTC = (uint32_t) tempval;
            return    SUCCESS;
        }

        break;

// Error parameter
        default:
            break;
}

    return ERROR;
}

/**
 * @}
 */


/* Public Functions ----------------------------------------------------------- */
/** @addtogroup WDT_Public_Functions
 * @{
 */


/*********************************************************************//**
* @brief         Initial for Watchdog function
*                     Clock source = RTC ,
*
* @param[in]    ClkSrc  Select clock source
*                 -    0:Clock source from Internal RC oscillator
*                 -    1: Selects the APB peripheral clock (PCLK)
*                 -    2:Selects the RTC oscillator
*
* @param[in]    WDTMode WDT mode
*                 -    0: Use WDT to generate interrupt only
*                 -    1:WDT_MODE_RESET
* @return         None
 **********************************************************************/
void WDT_Init (uint32_t ClkSrc, uint32_t WDTMode)
{
    CHECK_PARAM(PARAM_WDT_CLK_OPT(ClkSrc));
    CHECK_PARAM(PARAM_WDT_MODE_OPT(WDTMode));
    CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_4);

    //Set clock source
    LPC_WDT->WDCLKSEL &= ~WDT_WDCLKSEL_MASK;
    LPC_WDT->WDCLKSEL |= ClkSrc;
    //Set WDT mode
    if (WDTMode == WDT_MODE_RESET){
        LPC_WDT->WDMOD |= WDT_WDMOD_WDRESET;
    }
}

/*********************************************************************//**
* @brief         Start WDT activity with given timeout value
* @param[in]    TimeOut WDT reset after timeout if it is not feed
* @return         None
 **********************************************************************/
void WDT_Start(uint32_t TimeOut)
{
    uint32_t ClkSrc;

    ClkSrc = LPC_WDT->WDCLKSEL;
    ClkSrc &=WDT_WDCLKSEL_MASK;
    WDT_SetTimeOut(ClkSrc,TimeOut);
    //enable watchdog
    LPC_WDT->WDMOD |= WDT_WDMOD_WDEN;
    WDT_Feed();
}

/********************************************************************//**
 * @brief         Read WDT Time out flag
 * @param[in]    None
 * @return        Time out flag status of WDT
 *********************************************************************/
FlagStatus WDT_ReadTimeOutFlag (void)
{
    return ((LPC_WDT->WDMOD & WDT_WDMOD_WDTOF) != 0) ? SET : RESET;
}

/********************************************************************//**
 * @brief         Clear WDT Time out flag
 * @param[in]    None
 * @return        None
 *********************************************************************/
void WDT_ClrTimeOutFlag (void)
{
    LPC_WDT->WDMOD &=~WDT_WDMOD_WDTOF;
}

/********************************************************************//**
 * @brief         Update WDT timeout value and feed
 * @param[in]    TimeOut    TimeOut value to be updated
 * @return        None
 *********************************************************************/
void WDT_UpdateTimeOut ( uint32_t TimeOut)
{
    uint32_t ClkSrc;
    ClkSrc = LPC_WDT->WDCLKSEL;
    ClkSrc &=WDT_WDCLKSEL_MASK;
    WDT_SetTimeOut(ClkSrc,TimeOut);
    WDT_Feed();
}


/********************************************************************//**
 * @brief         After set WDTEN, call this function to start Watchdog
 *                 or reload the Watchdog timer
 * @param[in]    None
 *
 * @return        None
 *********************************************************************/
void WDT_Feed (void)
{
    // Disable irq interrupt
    __disable_irq();
    LPC_WDT->WDFEED = 0xAA;
    LPC_WDT->WDFEED = 0x55;
    // Then enable irq interrupt
    __enable_irq();
}

/********************************************************************//**
 * @brief         Get the current value of WDT
 * @param[in]    None
 * @return        current value of WDT
 *********************************************************************/
uint32_t WDT_GetCurrentCount(void)
{
    return LPC_WDT->WDTV;
}

/**
 * @}
 */

#endif /* _WDT */

/**
 * @}
 */

/* --------------------------------- End Of File ------------------------------ */