请问如何将LPTMR配置成1MS中断一次，时钟源为8MHZ的OSCERCLK

lgkgkfg

还有如何清除中断标志，请不要再评论说看官网的例子了，谢谢。

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1. /*
   
2. * Copyright (c) 2015, Freescale Semiconductor, Inc.
   
3. * All rights reserved.
   
4. *
   
5. * Redistribution and use in source and binary forms, with or without modification,
   
6. * are permitted provided that the following conditions are met:
   
7. *
   
8. * o Redistributions of source code must retain the above copyright notice, this list
   
9. *   of conditions and the following disclaimer.
   
10. *
    
11. * o Redistributions in binary form must reproduce the above copyright notice, this
    
12. *   list of conditions and the following disclaimer in the documentation and/or
    
13. *   other materials provided with the distribution.
    
14. *
    
15. * o Neither the name of Freescale Semiconductor, Inc. nor the names of its
    
16. *   contributors may be used to endorse or promote products derived from this
    
17. *   software without specific prior written permission.
    
18. *
    
19. * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
    
20. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    
21. * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    
22. * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
    
23. * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    
24. * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    
25. * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
    
26. * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    
27. * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    
28. * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    
29. */
    
30. 
    
31. #include "fsl_debug_console.h"
    
32. #include "board.h"
    
33. 
    
34. #include "fsl_lptmr.h"
    
35. #include "fsl_gpio.h"
    
36. 
    
37. #include "pin_mux.h"
    
38. #include "clock_config.h"
    
39. /*******************************************************************************
    
40. * Definitions
    
41. ******************************************************************************/
    
42. #define LPTMR_LED_HANDLER LPTMR0_IRQHandler
    
43. /* Get source clock for LPTMR driver */
    
44. #define LPTMR_SOURCE_CLOCK CLOCK_GetFreq(kCLOCK_LpoClk)
    
45. /* Define LPTMR microseconds counts value */
    
46. #define LPTMR_USEC_COUNT 1000000U
    
47. #define LED_INIT() LED_RED_INIT(LOGIC_LED_ON)
    
48. #define LED_TOGGLE() LED_RED_TOGGLE()
    
49. 
    
50. /*******************************************************************************
    
51. * Prototypes
    
52. ******************************************************************************/
    
53. 
    
54. /*******************************************************************************
    
55. * Variables
    
56. ******************************************************************************/
    
57. 
    
58. volatile uint32_t lptmrCounter = 0U;
    
59. 
    
60. /*******************************************************************************
    
61. * Code
    
62. ******************************************************************************/
    
63. void LPTMR_LED_HANDLER(void)
    
64. {
    
65.     LPTMR_ClearStatusFlags(LPTMR0, kLPTMR_TimerCompareFlag);
    
66.     lptmrCounter++;
    
67.     LED_TOGGLE();
    
68. }
    
69. 
    
70. /*!
    
71. * @brief Main function
    
72. */
    
73. int main(void)
    
74. {
    
75.     uint32_t currentCounter = 0U;
    
76.     lptmr_config_t lptmrConfig;
    
77. 
    
78.     LED_INIT();
    
79. 
    
80.     /* Board pin, clock, debug console init */
    
81.     BOARD_InitPins();
    
82.     BOARD_BootClockRUN();
    
83.     BOARD_InitDebugConsole();
    
84. 
    
85.     /* Configure LPTMR */
    
86.     /*
    
87.      * lptmrConfig.timerMode = kLPTMR_TimerModeTimeCounter;
    
88.      * lptmrConfig.pinSelect = kLPTMR_PinSelectInput_0;
    
89.      * lptmrConfig.pinPolarity = kLPTMR_PinPolarityActiveHigh;
    
90.      * lptmrConfig.enableFreeRunning = false;
    
91.      * lptmrConfig.bypassPrescaler = true;
    
92.      * lptmrConfig.prescalerClockSource = kLPTMR_PrescalerClock_1;
    
93.      * lptmrConfig.value = kLPTMR_Prescale_Glitch_0;
    
94.      */
    
95.     LPTMR_GetDefaultConfig(&lptmrConfig);
    
96. 
    
97.     /* Initialize the LPTMR */
    
98.     LPTMR_Init(LPTMR0, &lptmrConfig);
    
99. 
    
100.     /* Set timer period */
     
101.     LPTMR_SetTimerPeriod(LPTMR0, USEC_TO_COUNT(LPTMR_USEC_COUNT, LPTMR_SOURCE_CLOCK));
     
102. 
     
103.     /* Enable timer interrupt */
     
104.     LPTMR_EnableInterrupts(LPTMR0, kLPTMR_TimerInterruptEnable);
     
105. 
     
106.     /* Enable at the NVIC */
     
107.     EnableIRQ(LPTMR0_IRQn);
     
108. 
     
109.     PRINTF("Low Power Timer Example\r\n");
     
110. 
     
111.     /* Start counting */
     
112.     LPTMR_StartTimer(LPTMR0);
     
113.     while (1)
     
114.     {
     
115.         if (currentCounter != lptmrCounter)
     
116.         {
     
117.             currentCounter = lptmrCounter;
     
118.             PRINTF("LPTMR interrupt No.%d \r\n", currentCounter);
     
119.         }
     
120.     }
     
121. }
     

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不知道这样是否否和LZ的胃口，具体操作了那一部分对着代码，理解手册