Diff: lpc17xx_wdt.c

Revision:

0:84d7747641aa

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lpc17xx_wdt.c	Sun Mar 20 18:45:15 2011 +0000
@@ -0,0 +1,261 @@
+/***********************************************************************//**
+ * @file		lpc17xx_wdt.c
+ * @brief		Contains all functions support for WDT firmware library on LPC17xx
+ * @version		2.0
+ * @date		21. May. 2010
+ * @author		NXP MCU SW Application Team
+ **************************************************************************
+ * 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 ---------------------------------------------------------- */
+
+static uint8_t WDT_SetTimeOut (uint8_t clk_source, uint32_t timeout);
+
+/********************************************************************//**
+ * @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
+ *********************************************************************/
+static 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;
+}
+
+/* End of Private Functions --------------------------------------------------- */
+
+
+/* Public Functions ----------------------------------------------------------- */
+/** @addtogroup WDT_Public_Functions
+ * @{
+ */
+
+
+/*********************************************************************//**
+* @brief 		Initial for Watchdog function
+* 					Clock source = RTC ,
+* @param[in]	ClkSrc  Select clock source, should be:
+* 				- WDT_CLKSRC_IRC: Clock source from Internal RC oscillator
+* 				- WDT_CLKSRC_PCLK: Selects the APB peripheral clock (PCLK)
+* 				- WDT_CLKSRC_RTC: Selects the RTC oscillator
+* @param[in]	WDTMode WDT mode, should be:
+* 				- WDT_MODE_INT_ONLY: Use WDT to generate interrupt only
+* 				- WDT_MODE_RESET: Use WDT to generate interrupt and reset MCU
+* @return 		None
+ **********************************************************************/
+void WDT_Init (WDT_CLK_OPT ClkSrc, WDT_MODE_OPT 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(WDTMode);
+	}
+}
+
+/*********************************************************************//**
+* @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 ((FlagStatus)((LPC_WDT->WDMOD & WDT_WDMOD_WDTOF) >>2));
+}
+
+/********************************************************************//**
+ * @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 ------------------------------ */