MKL25-Low-Power Timer (LPTMR)

　　1、.c文件，该定时器配置为计数模式，每次定时周期到将响应中断

/*
 * lptmr.c
 *
 *  Created on: 2020年8月19日
 *      Author: Mr.W
 */
#include "lptmr.h"
#include "fsl_gpio.h"

/***********************************************************************************************************************
 * LPTMR0 initialization code
 **********************************************************************************************************************/
/* clang-format off */
/* TEXT BELOW IS USED AS SETTING FOR TOOLS *************************************
instance:
- name: 'LPTMR0'
- type: 'lptmr'
- mode: 'LPTMR_GENERAL'
- custom_name_enabled: 'false'
- type_id: 'lptmr_2eeab91a1a42f8238f9ac768f18c65ae'
- functional_group: 'BOARD_InitPeripherals'
- peripheral: 'LPTMR0'
- config_sets:
  - fsl_lptmr:
    - lptmr_config:
      - timerMode: 'kLPTMR_TimerModeTimeCounter'
      - pinSelect: 'ALT.0'
      - pinPolarity: 'kLPTMR_PinPolarityActiveHigh'
      - enableFreeRunning: 'false'
      - bypassPrescaler: 'true'
      - prescalerClockSource: 'kLPTMR_PrescalerClock_1'
      - clockSource: 'BOARD_BootClockRUN'
      - value: 'kLPTMR_Prescale_Glitch_0'
      - timerPeriod: '10000 us'
    - enableInterrupt: 'true'
    - interrupt:
      - IRQn: 'LPTMR0_IRQn'
      - enable_priority: 'false'
      - priority: '0'
      - enable_custom_name: 'false'
 * BE CAREFUL MODIFYING THIS COMMENT - IT IS YAML SETTINGS FOR TOOLS **********/
/* clang-format on */
const lptmr_config_t LPTMR0_config = {
  .timerMode = kLPTMR_TimerModeTimeCounter,
  .pinSelect = kLPTMR_PinSelectInput_0,
  .pinPolarity = kLPTMR_PinPolarityActiveHigh,
  .enableFreeRunning = false,
  .bypassPrescaler = true,
  .prescalerClockSource = kLPTMR_PrescalerClock_1,
  .value = kLPTMR_Prescale_Glitch_0
};

void lptmr0_init(void) {
  /* Initialize the LPTMR */
  LPTMR_Init(LPTMR0_PERIPHERAL, &LPTMR0_config);
  /* Set LPTMR period
   * Note : the parameter "ticks" of LPTMR_SetTimerPeriod should be equal or greater than 1.
   */
  LPTMR_SetTimerPeriod(LPTMR0_PERIPHERAL, USEC_TO_COUNT(LPTMR0_USEC_COUNT, LPTMR0_CLK_FREQ));
  /* Configure timer interrupt */
  LPTMR_EnableInterrupts(LPTMR0_PERIPHERAL, kLPTMR_TimerInterruptEnable);
  /* 在使能LPTMR0_IRQn中断前需要先清除该中断,否则会出现打开定时器就进入中断的问题 */
  NVIC_ClearPendingIRQ(LPTMR0_IRQn);
  /* Enable interrupt LPTMR0_IRQn request in the NVIC */
  EnableIRQ(LPTMR0_IRQn);
}

void lptmr0_start(void)
{
    LPTMR_StartTimer(LPTMR0_PERIPHERAL);
}

void lptmr0_stop(void)
{
    LPTMR_StopTimer(LPTMR0_PERIPHERAL);
}


void LPTMR0_IRQHandler(void)
{
    LPTMR_ClearStatusFlags(LPTMR0_PERIPHERAL, kLPTMR_TimerCompareFlag);

    GPIO_TogglePinsOutput(GPIOB, 1 << 18);
}

 

　　2、.h文件

/*
 * lptmr.h
 *
 *  Created on: 2020年8月19日
 *      Author: Mr.W
 */

#ifndef LPTMR_H_
#define LPTMR_H_

/***********************************************************************************************************************
 * Included files
 **********************************************************************************************************************/
#include "fsl_common.h"
#include "fsl_lptmr.h"

#if defined(__cplusplus)
extern "C" {
#endif /* __cplusplus */

/***********************************************************************************************************************
 * Definitions
 **********************************************************************************************************************/
/* Definitions for BOARD_InitPeripherals functional group */
/* BOARD_InitPeripherals defines for LPTMR0 */
/* Definition of peripheral ID */
#define LPTMR0_PERIPHERAL LPTMR0
/* Definition of the clock source frequency */
#define LPTMR0_CLK_FREQ 1000UL
/* Definition of the prescaled clock source frequency */
#define LPTMR0_INPUT_FREQ 1000UL
/* Definition of the timer period in us */
#define LPTMR0_USEC_COUNT 10000UL
/* Definition of the timer period in number of ticks */
#define LPTMR0_TICKS 10UL
/* LPTMR0 interrupt vector ID (number). */
#define LPTMR0_IRQN LPTMR0_IRQn
/* LPTMR0 interrupt handler identifier. */
#define LPTMR0_IRQHANDLER LPTMR0_IRQHandler

/***********************************************************************************************************************
 * Global variables
 **********************************************************************************************************************/
extern const lptmr_config_t LPTMR0_config;

/***********************************************************************************************************************
 * Initialization functions
 **********************************************************************************************************************/
void lptmr0_init(void);
void lptmr0_start(void);
void lptmr0_stop(void);

#if defined(__cplusplus)
}
#endif

#endif /* LPTMR_H_ */

 

#end