标题: STM32H750单片机LPUART+BDMA控制程序 [打印本页]
作者: 辉耀石    时间: 2025-4-30 11:21
标题: STM32H750单片机LPUART+BDMA控制程序
STM32H750 LPUART + BDMA 控制，认证 BDMA 使用
注意：BDMA 只能使用 SRAM4

  1. #include "cspDwt.h"

  3. #include <stdio.h>

  5. #include "stm32h7xx_hal.h"

  7. /* mdk 下载需要 勾选 Stop After Reset */

  9. /* DWT 计时功能 */
  10. typedef struct
  11. {
  12.     unsigned char count;
  13.     unsigned int note[DWT_NOTE_MAX_NUMBER + 1];
  14.    
  15. }Ctrl_t;

  17. static Ctrl_t s_ctrl = {0};
  18. static Ctrl_t *p = &s_ctrl;

  20. /* ----- DWT 延时 -----        */
  21. #define  DWT_CR             *(volatile uint32_t *)0xE0001000
  22. #define  DWT_CYCCNT         *(volatile uint32_t *)0xE0001004
  23. #define  DEM_CR             *(volatile uint32_t *)0xE000EDFC
  24. #define  DEM_CR_TRCENA      (1 << 24)
  25. #define  DWT_CR_CYCCNTENA   (1 <<  0)

  27. /**
  28. * @brief  DWT 延时初始化
  29. * @param  void
  30. * @return void
  31. */
  32. void cDwt_Init(void)
  33. {
  34.     DEM_CR |= DEM_CR_TRCENA;
  35.     DWT_CR |= DWT_CR_CYCCNTENA;
  36. }

  38. /**
  39. * @brief  DWT 微秒延时
  40. * @param  US 延时计数
  41. * @return void
  42. */
  43. void cDwt_DelayUs(unsigned int us)
  44. {
  45.     unsigned int startTime = DWT_CYCCNT;
  46.     unsigned int time =  us * (SystemCoreClock / (1000000));
  47.     unsigned int endTime = startTime + time;
  48.    
  49.     if (endTime > startTime)
  50.     {
  51.         while ((DWT_CYCCNT > startTime) && (DWT_CYCCNT < endTime));
  52.     }
  53.     else
  54.     {
  55.         while ((DWT_CYCCNT > startTime) && (DWT_CYCCNT < endTime));
  56.     }
  57. }

  59. /**
  60. * @brief  DWT 毫秒延时
  61. * @param  MS 延时计数
  62. * @return void
  63. */
  64. void cDwt_DelayMs(unsigned int ms)
  65. {
  66.     for(unsigned int i = 0; i < ms; i++)
  67.     {
  68.         cDwt_DelayUs(1000);
  69.     }
  70. }

  72. /* 计时结束清零 */
  73. void cDwt_Start(void)
  74. {
  75.     p->count = 1;
  76.     p->note[0] = DWT_CYCCNT;
  77. }

  79. /* 计时打点 */
  80. void cDwt_Note(void)
  81. {
  82.     if (p->count >= DWT_NOTE_MAX_NUMBER)
  83.     {
  84.         printf("%s 计时失败 计时点不足\r\n", __func__);
  85.     }
  86.    
  87.     p->note[p->count] = DWT_CYCCNT;
  88.     p->count++;
  89. }

  91. /* 计时结束 + 打印时间参数 */
  92. void cDwt_End(void)
  93. {
  94.     unsigned int coreClock = HAL_RCC_GetSysClockFreq() / 1000000;
  95.     unsigned int realCount = 0;
  96.     unsigned int totalUs = 0;
  97.     unsigned int showUs = 0;
  98.     unsigned int showMs = 0;
  99.     unsigned int showS = 0;
  100.     for (int i = 0; i < p->count; i++)
  101.     {
  102.         /* 判断时钟是否重新计时 */
  103.         if (p->note[i] < p->note[0])
  104.         {
  105.             realCount = 0xFFFFFFFF - p->note[0] + p->note[i];
  106.         }
  107.         else
  108.         {
  109.             realCount = p->note[i] - p->note[0];
  110.         }
  111.         
  112.         totalUs = realCount / coreClock;
  113.         showS = totalUs / 1000000;
  114.         showMs = (totalUs - showS * 1000000) / 1000;
  115.         showUs = (totalUs - showS * 1000000 - showMs * 1000);
  116.         printf("Time[%d]-[%d]s-[%d]ms-[%d]us\r\n", i, showS, showMs, showUs);
  117.     }
  118. }



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代码: STM32H750VB_CubeMx_LPUART_BDMA.7z (812.65 KB, 下载次数: 0)




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