STM32学习日志--使用DMA功能自动更新PWM的输出

/*******************************************************************************
 编译环境: EWARM V5.30
 硬件环境: DZY2.PCB
 STM32 FW:   V3.0.0
 作者 : szlihongtao
 ******************************************************************************
 REV  : V1.00
 DATE : 2011-04-18
 NOTE :  
 *******************************************************************************/
#include "stm32f10x.h"
#include "stm32_m.h"
#include "dzy.h"   
#include "myRCC.h"   
//******************************************************************************
#define TIM1_CCR3_Address    0x40012C3C

bit f_tb;    // 基本定时标志
bit f_100ms, f_1000ms;
INT16U cnt_test;  // 计数器，仅供软件调试使用
float clk_sys;   // 仅供软件调试使用
#if 1
uint16_t SRC_Buffer[ ] =
{ 72 * 5 };   // 由于载波频率取20kHZ，所以最大脉冲宽度不要超50us,即常数不要超过72*50
#else
uint16_t SRC_Buffer[]=
{ 72*2,72*5,72*10,72*20,72*40,72*10}; // 由于载波频率取20kHZ，所以最大脉冲宽度不要超50us,即常数不要超过72*50
#endif
//******************************************************************************
// 延时程序，单位为*1ms
//******************************************************************************
void delayms( INT16U cnt )
{
//#define   CONST_1MS  7333   // 72MhZ
//#define   CONST_1MS 3588   // 32MhZ
#define   CONST_1MS (105*FCLK) 
  
  INT16U i;
  
  __no_operation( );
  while ( cnt-- )
    for ( i = 0; i < CONST_1MS; i++ )
      ;
}
//******************************************************************************
// pcb上的指示灯
//******************************************************************************
static void led_toggle( void )
{
  GPIOC->ODR ^= GPIO_Pin_7;  // led2 toogle
  GPIOC->ODR ^= GPIO_Pin_6;  // led3 toogle
}
//******************************************************************************
// 时钟设置初始化
//******************************************************************************
static void RCC_Configuration( void )
{
  ErrorStatus HSEStartUpStatus;
  /*
   RCC_AdjustHSICalibrationValue 调整内部高速晶振（HSI）校准值
   RCC_ITConfig 使能或者失能指定的RCC中断
   RCC_ClearFlag 清除RCC的复位标志位
   RCC_GetITStatus 检查指定的RCC中断发生与否
   RCC_ClearITPendingBit 清除RCC的中断待处理位
   */
  /* RCC system reset(for debug purpose) */
  // 时钟系统复位
  RCC_DeInit( );
  
  // 使能外部的8M晶振
  // 设置外部高速晶振（HSE）
  /* Enable HSE */
  RCC_HSEConfig( RCC_HSE_ON );
  
  // 使能或者失能内部高速晶振（HSI）
  RCC_HSICmd( DISABLE );
  
  // 等待HSE起振
  // 该函数将等待直到HSE就绪，或者在超时的情况下退出
  /* Wait till HSE is ready */
  HSEStartUpStatus = RCC_WaitForHSEStartUp( );
  
  if ( HSEStartUpStatus == SUCCESS )
  {
    // 设置AHB时钟（HCLK）
    RCC_HCLKConfig( RCC_HCLK_Div_ ); // 36 MHz
      
    // 设置低速AHB时钟（PCLK1）
    RCC_PCLK1Config( RCC_PCLK1_Div_ ); // 2.25 MHz
      
    // 设置高速AHB时钟（PCLK2）
    RCC_PCLK2Config( RCC_PCLK2_Div_ ); // 2.25 MHz
      
    /* ADCCLK = PCLK2/8 */
    // 设置ADC时钟（ADCCLK）
    RCC_ADCCLKConfig( RCC_ADC_DIV_ ); // 0.281Mhz
      
    // 设置USB时钟（USBCLK）
    // USB时钟 = PLL时钟除以1.5
    //RCC_USBCLKConfig(RCC_USBCLKSource_PLLCLK_1Div5);
    
    // 设置外部低速晶振（LSE）
    RCC_LSEConfig( RCC_LSE_OFF );
    
    // 使能或者失能内部低速晶振（LSI）
    // LSE晶振OFF
    RCC_LSICmd( DISABLE );
    
    // 设置RTC时钟（RTCCLK）
    // 选择HSE时钟频率除以128作为RTC时钟
    //RCC_RTCCLKConfig(RCC_RTCCLKSource_HSE_Div128);
    
    // 使能或者失能RTC时钟
    // RTC时钟的新状态
    RCC_RTCCLKCmd( DISABLE );
    
    /* Flash 2 wait state */
    FLASH_SetLatency( FLASH_Latency_2 );
    
    /* Enable Prefetch Buffer */
    FLASH_PrefetchBufferCmd( FLASH_PrefetchBuffer_Enable );
    
    /* PLLCLK = 8MHz * 9 = 72 MHz */
    // 设置PLL时钟源及倍频系数
    RCC_PLLConfig( RCC_PLLSource_HSE_Div1, RCC_PLLMul_ );
    
    /* Enable PLL */
    // 使能或者失能PLL
    RCC_PLLCmd( ENABLE );
    
    /* Wait till PLL is ready */
    // 检查指定的RCC标志位设置与否
    while ( RCC_GetFlagStatus( RCC_FLAG_PLLRDY ) == RESET )
    {
    }
    
    /* Select PLL as system clock source */
    // 设置系统时钟（SYSCLK）
    RCC_SYSCLKConfig( RCC_SYSCLKSource_PLLCLK );
    
    /* Wait till PLL is used as system clock source */
    // 返回用作系统时钟的时钟源
    while ( RCC_GetSYSCLKSource( ) != 0x08 )
    {
    }
  }
  
  // 使能或者失能AHB外设时钟
  RCC_AHBPeriphClockCmd(
    RCC_AHBPeriph_DMA1 | RCC_AHBPeriph_DMA2 | RCC_AHBPeriph_SRAM
      | RCC_AHBPeriph_FLITF | RCC_AHBPeriph_CRC | RCC_AHBPeriph_FSMC
      | RCC_AHBPeriph_SDIO, DISABLE );
  // 使能或者失能APB1外设时钟
  RCC_APB1PeriphClockCmd( RCC_APB1Periph_ALL, DISABLE );
  
  // 强制或者释放高速APB（APB2）外设复位
  RCC_APB2PeriphResetCmd( RCC_APB2Periph_ALL, ENABLE );
  // 退出复位状态
  RCC_APB2PeriphResetCmd( RCC_APB2Periph_ALL, DISABLE );
  
  // 强制或者释放低速APB（APB1）外设复位
  RCC_APB1PeriphResetCmd( RCC_APB1Periph_ALL, ENABLE );
  
  // 强制或者释放后备域复位
  RCC_BackupResetCmd( ENABLE );
  
  // 使能或者失能时钟安全系统
  RCC_ClockSecuritySystemCmd( DISABLE );
}
//******************************************************************************
// NVIC设置
//******************************************************************************
void NVIC_Configuration( void )
{
  NVIC_InitTypeDef NVIC_InitStructure;
  
  /* Configure one bit for preemption priority */
  NVIC_PriorityGroupConfig( NVIC_PriorityGroup_1 );
  
  NVIC_InitStructure.NVIC_IRQChannel = TIM1_UP_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  //NVIC_Init(&NVIC_InitStructure);
  
  NVIC_InitStructure.NVIC_IRQChannel = TIM1_CC_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  //NVIC_Init(&NVIC_InitStructure);
  
  NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel5_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init( &NVIC_InitStructure );
}
//******************************************************************************
// SysTick设置初始化
//******************************************************************************
static void SysTick_Config1( void )
{
#if 1
#define SystemFreq  (FCLK*1000000.0)    // 单位为Hz
#define TB_SysTick  (TIME_TB*1000)  // 单位为uS,与示波器实测一致
  
  static INT32U ticks;
  
  ticks = ( INT32U )( ( TB_SysTick / 1000000.0 ) * SystemFreq );
  SysTick_Config( ticks );
#endif 
}
//******************************************************************************
// GPIO设置
//******************************************************************************
static void GPIO_Configuration( void )
{
  GPIO_InitTypeDef GPIO_InitStructure;
  
  RCC_APB2PeriphClockCmd(
    RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC
      | RCC_APB2Periph_GPIOD | RCC_APB2Periph_AFIO, ENABLE );
  
//------------------------------------------------------------------------------
  GPIO_Write( GPIOA, 0xffff );
  
  /* GPIOA Configuration: Channel 3 as alternate function push-pull */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_Init( GPIOA, &GPIO_InitStructure );
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  // GPIO_Init(GPIOA, &GPIO_InitStructure);
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_Init( GPIOA, &GPIO_InitStructure );
//------------------------------------------------------------------------------
  
  GPIO_Write( GPIOB, 0xffff ); // 11111101-11111111     
    
  /* GPIOB Configuration: Channel 3N as alternate function push-pull */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_15;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_Init( GPIOB, &GPIO_InitStructure );
  //------------------------------------------------------------------------------
  
  GPIO_Write( GPIOC, 0xff0f ); // 11111111-00001111
    
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7 | GPIO_Pin_6 | GPIO_Pin_4
    | GPIO_Pin_5;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_Init( GPIOC, &GPIO_InitStructure );
//------------------------------------------------------------------------------
  GPIO_Write( GPIOD, 0xffff ); // 11111111-11111111  
    
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3 | GPIO_Pin_2;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
  GPIO_Init( GPIOD, &GPIO_InitStructure );
}
//******************************************************************************
void DMA_Configuration( void )
{
  DMA_InitTypeDef DMA_InitStructure;
  
  RCC_AHBPeriphClockCmd( RCC_AHBPeriph_DMA1, ENABLE );  // dma1时钟使能
    
  DMA_DeInit( DMA1_Channel5 );   // DMA复位
  DMA_StructInit( &DMA_InitStructure );   // DMA缺省的参数
    
  DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) TIM1_CCR3_Address; //外设地址
  DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t) SRC_Buffer;  //内存地址
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST; //dma传输方向,单向
  DMA_InitStructure.DMA_BufferSize = sizeof( SRC_Buffer ) / 2; //设置DMA在传输时缓冲区的长度
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //设置DMA的外设递增模式，一个外设
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;  //设置DMA的内存递增模式，
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; //外设数据字长
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;   //内存数据字长
  //循环模式开启，Buffer写满后，自动回到初始地址开始传输
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;  //设置DMA的传输模式
  DMA_InitStructure.DMA_Priority = DMA_Priority_High; //设置DMA的优先级别
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;  //设置DMA的2个memory中的变量互相访问
  DMA_Init( DMA1_Channel5, &DMA_InitStructure );
  
  DMA_ClearFlag( DMA1_IT_TC5 );
  DMA_ITConfig( DMA1_Channel5, DMA_IT_TC, ENABLE );
  
  DMA_Cmd( DMA1_Channel5, ENABLE );
}

/* TIM1 DMA Transfer example -------------------------------------------------
 TIM1CLK = 72 MHz, Prescaler = 0, TIM1 counter clock = 72 MHz 
 The TIM1 Channel3 is configured to generate a complementary PWM signal with 
 a frequency equal to: TIM1 counter clock / (TIM1_Period + 1) = 17.57 KHz and 
 a variable duty cycle that is changed by the DMA after a specific number of
 Update DMA request.
 The number of this repetitive requests is defined by the TIM1 Repetion counter,
 each 3 Update Requests, the TIM1 Channel 3 Duty Cycle changes to the next new 
 value defined by the SRC_Buffer . 
 -----------------------------------------------------------------------------*/
//******************************************************************************
void Tim1_Configuration( void )
{
  INT16U TIM_Prescaler, TIM_Period;
  INT32U utemp;
  TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
  TIM_OCInitTypeDef TIM_OCInitStructure;
  
  RCC_APB2PeriphClockCmd( RCC_APB2Periph_TIM1, ENABLE );
  
  TIM_DeInit( TIM1 );
  
  utemp = ( INT32U )( TIM1CLK * 1000000.0 ) / Freq_PWM;
  
  TIM_Prescaler = utemp / 65536;
  ++TIM_Prescaler;                       // 注意这句话，一定要++
  
  utemp = ( INT32U )( TIM1CLK * 1000000.0 ) / TIM_Prescaler;  // 分频后的定时器输入频率
  TIM_Period = utemp / Freq_PWM;               // 周期常数
    
  TIM_TimeBaseStructure.TIM_Period = TIM_Period - 1;
  TIM_TimeBaseStructure.TIM_Prescaler = TIM_Prescaler - 1;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_RepetitionCounter = 1 - 1;               // 每次直接更新
  TIM_TimeBaseInit( TIM1, &TIM_TimeBaseStructure );
//------------------------------------------------------------------------------
  /* PWM1 Mode configuration: Channel1 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; // 使能输出比较状态
  TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Disable; // 失能输出比较N状态
  TIM_OCInitStructure.TIM_Pulse = 72;
  /*           
   TIM_OCMode_PWM2  TIM_OCPolarity_Low    正脉冲模式 
   TIM_OCMode_PWM2  TIM_OCPolarity_High   负脉冲模式

   TIM_OCMode_PWM1  TIM_OCPolarity_Low    负脉冲模式
   TIM_OCMode_PWM1  TIM_OCPolarity_High   正脉冲模式

   TIM1_OCPolarity输出极性---TIM_OCPolarity_High，输出比较极性高,输出的是正脉冲
   TIM1_OCPolarity输出极性---TIM_OCPolarity_Low， 输出比较极性低,输出的是负脉冲
   */
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;
  TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_Low; // 互补输出极性
  // 选择空闲状态下的非工作状态
  // 当MOE=0设置TIM1输出比较空闲状态       
  // 默认输出位低电平                
  TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
  // 选择空闲状态下的非工作状态
  // 当MOE=0重置TIM1输出比较N空闲状态
  TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCNIdleState_Reset;
  TIM_OC3Init( TIM1, &TIM_OCInitStructure );
  TIM_OC3PreloadConfig( TIM1, TIM_OCPreload_Enable );   // 使能TIMx在CCR1上的预装载寄存器
    
  /* TIM1 Update DMA Request enable */
  TIM_DMACmd( TIM1, TIM_DMA_Update, ENABLE );
  
  //TIM_ITConfig(TIM1,TIM_IT_Update,ENABLE); // 定时中断使能
  //TIM_ITConfig(TIM1,TIM_IT_CC3,ENABLE); // 定时中断使能
  TIM_Cmd( TIM1, ENABLE );      // 定时器开始运行
    
  // 这条语句必须要有!!!
  TIM_CtrlPWMOutputs( TIM1, ENABLE ); /* Main Output Enable */
}
//******************************************************************************
// 基本定时程序,周期为 TIME_TB
//******************************************************************************
static func_tb( void )
{
  static INT16U tmr_100ms;
  static INT16U tmr_1000ms;
  
  if ( !f_tb )
    return;
  f_tb = 0;
  
  if ( ++tmr_100ms >= ( 100 / TIME_TB ) )
  {
    tmr_100ms = 0;
    f_100ms = 1;
    
    GPIOC->ODR ^= GPIO_Pin_4;  // led5 toogle          
  }
  if ( ++tmr_1000ms >= ( 1000 / TIME_TB ) )
  {
    tmr_1000ms = 0;
    f_1000ms = 1;
    GPIOC->ODR ^= GPIO_Pin_5;  // led4 toogle      
  }
}

//******************************************************************************
// 进入睡眠模式
// 自行编写
//******************************************************************************
void myPWR_EnterSleepMode( void )
{
  //PWR->CR |= CR_CWUF_Set; /* Clear Wake-up flag */
  
  /* Set SLEEPDEEP bit of Cortex System Control Register */
  //*(__IO uint32_t *) SCB_SysCtrl |= SysCtrl_SLEEPDEEP_Set;
  /* This option is used to ensure that store operations are completed */

  __WFI( ); /* Request Wait For Interrupt */
}
//******************************************************************************
// 主程序
//******************************************************************************
void main( void )
{
  int i;
  
  RCC_Configuration( );
  GPIO_Configuration( );
  delayms( 100 );   // 延时，等待电压稳定
  Tim1_Configuration( );
  DMA_Configuration( );
  SysTick_Config1( );
  NVIC_Configuration( );
//------------------------------------------------------------------------------ 
  for ( i = 0; i < 6; ++i )
  {
    //i=0;
    //GPIOA->ODR ^= GPIO_Pin_10;  // led3 toogle
    //GPIOA->ODR ^= GPIO_Pin_11;  // led3 toogle
    
    delayms( 1 );
    led_toggle( );
  }
//------------------------------------------------------------------------------  
  for ( ;; )
  {
    //if (set_sw&0x01)
    //myPWR_EnterSleepMode(); // 休眠，降低功耗
    
    func_tb( );
  }
}
//******************************************************************************
#ifdef  USE_FULL_ASSERT
/**
 * @brief  Reports the name of the source file and the source line number
 *   where the assert_param error has occurred.
 * @param file: pointer to the source file name
 * @param line: assert_param error line source number
 * @retval : None
 */
void assert_failed(uint8_t* file, uint32_t line)
{ 
  /* User can add his own implementation to report the file name and line number,
   ex: printf("Wrong parameters value: file %s on line %d
", file, line) */

  /* Infinite loop */
  while (1)
  { 
  }
}
#endif

/**
 ******************************************************************************
 * @file    Project/Template/stm32f10x_it.c
 * @author  MCD Application Team
 * @version V3.0.0
 * @date    04/06/2009
 * @brief   Main Interrupt Service Routines.
 *          This file provides template for all exceptions handler and
 *          peripherals interrupt service routine.
 ******************************************************************************
 * @copy
 *
 * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
 * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
 * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
 * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
 * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
 * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
 *
 * <h2><center>&copy; COPYRIGHT 2009 STMicroelectronics</center></h2>
 */

/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_it.h"
#include "stm32_m.h"

int tt;
extern bit f_tb;        // 基本定时标志
//******************************************************************************
/******************************************************************************/
/*            Cortex-M3 Processor Exceptions Handlers                         */
/******************************************************************************/

/**
 * @brief  This function handles NMI exception.
 * @param  None
 * @retval : None
 */
void NMI_Handler( void )
{
}

/**
 * @brief  This function handles Hard Fault exception.
 * @param  None
 * @retval : None
 */
void HardFault_Handler( void )
{
  /* Go to infinite loop when Hard Fault exception occurs */
  while ( 1 )
  {
  }
}

/**
 * @brief  This function handles Memory Manage exception.
 * @param  None
 * @retval : None
 */
void MemManage_Handler( void )
{
  /* Go to infinite loop when Memory Manage exception occurs */
  while ( 1 )
  {
  }
}

/**
 * @brief  This function handles Bus Fault exception.
 * @param  None
 * @retval : None
 */
void BusFault_Handler( void )
{
  /* Go to infinite loop when Bus Fault exception occurs */
  while ( 1 )
  {
  }
}

/**
 * @brief  This function handles Usage Fault exception.
 * @param  None
 * @retval : None
 */
void UsageFault_Handler( void )
{
  /* Go to infinite loop when Usage Fault exception occurs */
  while ( 1 )
  {
  }
}

/**
 * @brief  This function handles SVCall exception.
 * @param  None
 * @retval : None
 */
void SVC_Handler( void )
{
}

/**
 * @brief  This function handles Debug Monitor exception.
 * @param  None
 * @retval : None
 */
void DebugMon_Handler( void )
{
}

/**
 * @brief  This function handles PendSVC exception.
 * @param  None
 * @retval : None
 */
void PendSV_Handler( void )
{
}

/**
 * @brief  This function handles SysTick Handler.
 * @param  None
 * @retval : None
 */
void SysTick_Handler( void )
{
  f_tb = 1;
}
/******************************************************************************/
/*                 STM32F10x Peripherals Interrupt Handlers                   */
/*  Add here the Interrupt Handler for the used peripheral(s) (PPP), for the  */
/*  available peripheral interrupt handler's name please refer to the startup */
/*  file (startup_stm32f10x_xx.s).                                            */
/******************************************************************************/
void TIM1_UP_IRQHandler( void )   // 实际测量，周期为50US
{
  tt = 1;
  TIM_ClearITPendingBit( TIM1, TIM_IT_Update );
}

/******************************************************************************/
void TIM1_CC_IRQHandler( void )
{
  tt = 2;
  TIM_ClearITPendingBit( TIM1, TIM_IT_CC3 );
} 


/******************************************************************************/
void DMA1_Channel5_IRQHandler( void )
{
  tt = 3;
  DMA_ClearITPendingBit( DMA1_IT_TC5 );
  GPIOA->ODR ^= GPIO_Pin_11;    // for test!
}
//******************************************************************************
/******************* (C) COPYRIGHT 2009 STMicroelectronics *****END OF FILE****/
//******************************************************************************