diff options
Diffstat (limited to 'arch/arm/lpc17xx/Drivers/source/lpc17xx_systick.c')
| -rw-r--r-- | arch/arm/lpc17xx/Drivers/source/lpc17xx_systick.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/arch/arm/lpc17xx/Drivers/source/lpc17xx_systick.c b/arch/arm/lpc17xx/Drivers/source/lpc17xx_systick.c new file mode 100644 index 0000000..5112679 --- /dev/null +++ b/arch/arm/lpc17xx/Drivers/source/lpc17xx_systick.c @@ -0,0 +1,180 @@ +/***********************************************************************//**
+ * @file lpc17xx_systick.c
+ * @brief Contains all functions support for SYSTICK 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 SYSTICK
+ * @{
+ */
+
+/* Includes ------------------------------------------------------------------- */
+#include "lpc17xx_systick.h"
+#include "lpc17xx_clkpwr.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 _SYSTICK
+
+/* Public Functions ----------------------------------------------------------- */
+/** @addtogroup SYSTICK_Public_Functions
+ * @{
+ */
+/*********************************************************************//**
+ * @brief Initial System Tick with using internal CPU clock source
+ * @param[in] time time interval(ms)
+ * @return None
+ **********************************************************************/
+void SYSTICK_InternalInit(uint32_t time)
+{
+ uint32_t cclk;
+ float maxtime;
+
+ cclk = SystemCoreClock;
+ /* With internal CPU clock frequency for LPC17xx is 'SystemCoreClock'
+ * And limit 24 bit for RELOAD value
+ * So the maximum time can be set:
+ * 1/SystemCoreClock * (2^24) * 1000 (ms) + */
+ //check time value is available or not
+ maxtime = (1<<24)/(SystemCoreClock / 1000) ;
+ if(time > maxtime)
+ //Error loop
+ while(1);
+ else
+ {
+ //Select CPU clock is System Tick clock source
+ SysTick->CTRL |= ST_CTRL_CLKSOURCE;
+ /* Set RELOAD value
+ * RELOAD = (SystemCoreClock/1000) * time - 1
+ * with time base is millisecond + */
+ SysTick->RELOAD = (cclk/1000)*time - 1;
+ }
+}
+
+/*********************************************************************//**
+ * @brief Initial System Tick with using external clock source
+ * @param[in] freq external clock frequency(Hz)
+ * @param[in] time time interval(ms)
+ * @return None
+ **********************************************************************/
+void SYSTICK_ExternalInit(uint32_t freq, uint32_t time)
+{
+ float maxtime;
+
+ /* With external clock frequency for LPC17xx is 'freq'
+ * And limit 24 bit for RELOAD value
+ * So the maximum time can be set:
+ * 1/freq * (2^24) * 1000 (ms)
+ */
+ //check time value is available or not
+ maxtime = (1<<24)/(freq / 1000) ;
+ if (time>maxtime)
+ //Error Loop
+ while(1);
+ else
+ {
+ //Select external clock is System Tick clock source
+ SysTick->CTRL &= ~ ST_CTRL_CLKSOURCE;
+ /* Set RELOAD value
+ * RELOAD = (freq/1000) * time - 1
+ * with time base is millisecond
+ */
+ maxtime = (freq/1000)*time - 1;
+ SysTick->RELOAD = (freq/1000)*time - 1;
+ }
+}
+
+/*********************************************************************//**
+ * @brief Enable/disable System Tick counter
+ * @param[in] NewState System Tick counter status, should be:
+ * - ENABLE
+ * - DISABLE
+ * @return None
+ **********************************************************************/
+void SYSTICK_Cmd(FunctionalState NewState)
+{
+ CHECK_PARAM(PARAM_FUNCTIONALSTATE(NewState));
+
+ if(NewState == ENABLE)
+ //Enable System Tick counter
+ SysTick->CTRL |= ST_CTRL_ENABLE;
+ else
+ //Disable System Tick counter
+ SysTick->CTRL &= ~ST_CTRL_ENABLE;
+}
+
+/*********************************************************************//**
+ * @brief Enable/disable System Tick interrupt
+ * @param[in] NewState System Tick interrupt status, should be:
+ * - ENABLE
+ * - DISABLE
+ * @return None
+ **********************************************************************/
+void SYSTICK_IntCmd(FunctionalState NewState)
+{
+ CHECK_PARAM(PARAM_FUNCTIONALSTATE(NewState));
+
+ if(NewState == ENABLE)
+ //Enable System Tick counter
+ SysTick->CTRL |= ST_CTRL_TICKINT;
+ else
+ //Disable System Tick counter
+ SysTick->CTRL &= ~ST_CTRL_TICKINT;
+}
+
+/*********************************************************************//**
+ * @brief Get current value of System Tick counter
+ * @param[in] None
+ * @return current value of System Tick counter
+ **********************************************************************/
+uint32_t SYSTICK_GetCurrentValue(void)
+{
+ return (SysTick->CURR);
+}
+
+/*********************************************************************//**
+ * @brief Clear Counter flag
+ * @param[in] None
+ * @return None
+ **********************************************************************/
+void SYSTICK_ClearCounterFlag(void)
+{
+ SysTick->CTRL &= ~ST_CTRL_COUNTFLAG;
+}
+/**
+ * @}
+ */
+
+#endif /* _SYSTICK */
+
+/**
+ * @}
+ */
+
+/* --------------------------------- End Of File ------------------------------ */
+
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