TIM级联问题

jacky0505

请问,如果时钟为72MHz, TIM2作为主模式, TIM3作为从模式 :门控模式时, TIM3的计数时钟是不是也是72MHz?

在上面的情况下 ,再用TIM3作为TIM4的触发输入,TIM同样为门控模式, 那么TIM4的计数时钟会不会也是72MHz呢??

  TIM_TimeBaseStructure.TIM_Period = 20000;

  TIM_TimeBaseStructure.TIM_Prescaler = 0;

  TIM_TimeBaseStructure.TIM_ClockDivision = 0;

  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

  TIM_TimeBaseStructure.TIM_Period = 1000;

  TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

  TIM_TimeBaseStructure.TIM_Period = 9;

  TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);

  /* Master Configuration in PWM1 Mode */

  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

  TIM_OCInitStructure.TIM_Pulse = 15000;

  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;

  TIM_OC1Init(TIM2, &TIM_OCInitStructure);

  /* Select the Master Slave Mode */

  TIM_SelectMasterSlaveMode(TIM2, TIM_MasterSlaveMode_Enable);

  /* Master Mode selection */

  TIM_SelectOutputTrigger(TIM2, TIM_TRGOSource_Update);                     

  /* Slaves Configuration: PWM1 Mode */

  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

  TIM_OCInitStructure.TIM_Pulse = 500;

  TIM_OC1Init(TIM3, &TIM_OCInitStructure);

  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

  TIM_OCInitStructure.TIM_Pulse = 5;

  TIM_OC1Init(TIM4, &TIM_OCInitStructure);

  /* Slave Mode selection: TIM3 */

  TIM_SelectSlaveMode(TIM3, TIM_SlaveMode_Gated);

  TIM_SelectInputTrigger(TIM3, TIM_TS_ITR1);                                  

  /* Select the Master Slave Mode */

  TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable);

  /* Master Mode selection: TIM3 */

  TIM_SelectOutputTrigger(TIM3, TIM_TRGOSource_Update);  

  /* Slave Mode selection: TIM4 */

  TIM_SelectSlaveMode(TIM4, TIM_SlaveMode_Gated);

  TIM_SelectInputTrigger(TIM4, TIM_TS_ITR2);

  /* TIM enable counter */

  TIM_Cmd(TIM3, ENABLE);

  TIM_Cmd(TIM2, ENABLE);

  TIM_Cmd(TIM4, ENABLE);

正点原子

回复【楼主位】jacky0505:
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错.
只有TIM2的时钟为72M,TIM3的时钟就是TIM2的输出,TIM4的时钟就是TIM3的 输出.

jacky0505

回复【2楼】正点原子:
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那就怪了,为什么用keil仿真时,计算出的时钟是72MHz的

jacky0505

引用自 2楼 jacky0505 的回复:

回复【2楼】正点原子:
----------------------------
那就怪了,为什么用keil仿真时,TIM3计算出的时钟是72MHz的

正点原子

回复【4楼】jacky0505:
---------------------------------
那是因为你设置有误吧.
 

jacky0505

回复【5楼】正点原子:
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我是复制MDK例子里面的,只改过TIM_Period 这些,其它的都没改

zhang911

正点原子 发表于 2011-9-7 13:42
回复【楼主位】jacky0505:
---------------------------------
错.
只有TIM2的时钟为72M,TIM3的时钟就是TIM ...

/** @defgroup TIM_Internal_Trigger_Selection
  * @{
  */

#define TIM_TS_ITR0                        ((uint16_t)0x0000)
#define TIM_TS_ITR1                        ((uint16_t)0x0010)
#define TIM_TS_ITR2                        ((uint16_t)0x0020)
#define TIM_TS_ITR3                        ((uint16_t)0x0030)
#define TIM_TS_TI1F_ED                     ((uint16_t)0x0040)
#define TIM_TS_TI1FP1                      ((uint16_t)0x0050)
#define TIM_TS_TI2FP2                      ((uint16_t)0x0060)
#define TIM_TS_ETRF                        ((uint16_t)0x0070)
原子哥，这几个触发源都是什么意思？？