我想问大家一个问题
就是那个
STM32 官方的例程
tiM6 steps 中是怎样实现 六路波形有固定相位差输出?我没有看懂那个程序 尤其是 TIM_OCInitStructure.TIM_Pulse 的具体作用? 好像这个作用在这个程序里与别的程序不太一样啊,还有就是捕获比较通道与其互补的为什么没有实现互补输出而是移相了 请大家指教
程序如下:
#include "stm32f10x_lib.h"
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
u16 CCR1_Val = 32767;
u16 CCR2_Val = 24575;
u16 CCR3_Val = 16383;
u16 CCR4_Val = 8191;
ErrorStatus HSEStartUpStatus;
void RCC_Configuration(void);
void GPIO_Configuration(void);
void SysTick_Configuration(void);
void NVIC_Configuration(void);
int main(void)
{
#ifdef DEBUG
debug();
#endif
RCC_Configuration();
NVIC_Configuration();
GPIO_Configuration();
SysTick_Configuration();
/*-----------------------------------------------------------------------------
The STM32F10x TIM1 peripheral offers the possibility to program in advance the
configuration for the next TIM1 outputs behaviour (step) and change the configuration
of all the channels at the same time. This operation is possible when the COM
(commutation) event is used.
The COM event can be generated by software by setting the COM bit in the TIM1_EGR
register or by hardware (on TRC rising edge).
In this example, a software COM event is generated each 100 ms: using the Systick
interrupt.
The TIM1 is configured in Timing Mode, each time a COM event occurs,
a new TIM1 configuration will be set in advance.
The following Table describes the TIM1 Channels states:
-----------------------------------------------
| Step1 | Step2 | Step3 | Step4 | Step5 | Step6 |
----------------------------------------------------------
|Channel1 | 1 | 0 | 0 | 0 | 0 | 1 |
----------------------------------------------------------
|Channel1N | 0 | 0 | 1 | 1 | 0 | 0 |
----------------------------------------------------------
|Channel2 | 0 | 0 | 0 | 1 | 1 | 0 |
----------------------------------------------------------
|Channel2N | 1 | 1 | 0 | 0 | 0 | 0 |
----------------------------------------------------------
|Channel3 | 0 | 1 | 1 | 0 | 0 | 0 |
----------------------------------------------------------
|Channel3N | 0 | 0 | 0 | 0 | 1 | 1 |
----------------------------------------------------------
-----------------------------------------------------------------------------*/
TIM_TimeBaseStructure.TIM_Prescaler = 71;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseStructure.TIM_Period = 4095;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
/* Channel 1, 2,3 and 4 Configuration in PWM mode */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Timing;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_Pulse = 2047;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCNIdleState_Set;
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
TIM_OCInitStructure.TIM_Pulse = 1023;
TIM_OC2Init(TIM1, &TIM_OCInitStructure);
TIM_OCInitStructure.TIM_Pulse = 511;
TIM_OC3Init(TIM1, &TIM_OCInitStructure);
/* Automatic Output enable, Break, dead time and lock configuration*/
TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF;
TIM_BDTRInitStructure.TIM_DeadTime = 1;
TIM_BDTRInitStructure.TIM_Break = TIM_Break_Enable;
TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;
TIM_BDTRConfig(TIM1, &TIM_BDTRInitStructure);
TIM_CCPreloadControl(TIM1, ENABLE);
TIM_ITConfig(TIM1, TIM_IT_COM, ENABLE);
/* TIM1 counter enable */
TIM_Cmd(TIM1, ENABLE);
/* Main Output Enable */
TIM_CtrlPWMOutputs(TIM1, ENABLE);
while (1)
{}
}
void RCC_Configuration(void)
{
/* RCC system reset(for debug purpose) */
RCC_DeInit();
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);
/* Wait till HSE is ready */
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if (HSEStartUpStatus == SUCCESS)
{
/* Enable Prefetch Buffer */
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* Flash 2 wait state */
FLASH_SetLatency(FLASH_Latency_2);
/* HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
/* PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1);
/* PCLK1 = HCLK/2 */
RCC_PCLK1Config(RCC_HCLK_Div2);
/* PLLCLK = 8MHz * 9 = 72 MHz */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);
/* Enable PLL */
RCC_PLLCmd(ENABLE);
/* Wait till PLL is ready */
while (RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
{}
/* Select PLL as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* Wait till PLL is used as system clock source */
while (RCC_GetSYSCLKSource() != 0x08)
{}
}
/* TIM1, GPIOA and GPIOB clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1 | RCC_APB2Periph_GPIOA |
RCC_APB2Periph_GPIOB, ENABLE);
}
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* GPIOA Configuration: Channel 1, 2 and 3 as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9 | GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* GPIOB Configuration: Channel 1N, 2N and 3N as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
GPIO_Init(GPIOB, &GPIO_InitStructure);
/* GPIOB Configuration: BKIN pin */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOB, &GPIO_InitStructure);
}
void SysTick_Configuration(void)
{
/* Configure SysTick to generate an interrupt each 100ms (with HCLK = 72MHz) -*/
/* Select AHB clock(HCLK) as SysTick clock source */
SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK);
/* SysTick interrupt each 10 Hz with Core clock equal to 72MHz */
SysTick_SetReload(7200000);
/* Enable SysTick Counter */
SysTick_CounterCmd(SysTick_Counter_Enable);
/* Enable SysTick interrupt */
SysTick_ITConfig(ENABLE);
}
void NVIC_Configuration(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
#ifdef VECT_TAB_RAM
/* Set the Vector Table base location at 0x20000000 */
NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else /* VECT_TAB_FLASH */
/* Set the Vector Table base location at 0x08000000 */
NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif
/* Enable the TIM1 Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM1_TRG_COM_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
NVIC_SystemHandlerPriorityConfig(SystemHandler_SysTick, 0, 0);
}
#ifdef DEBUG
void assert_failed(u8* file, u32 line)
{
while (1)
{}
}
--------------------------】
是指输出波形的占空长度
可以参考一下这篇文章:
STM32 定时器产生PWM彻底应用:http://home.eeworld.com.cn/my/space-uid-320111-blogid-55195.html
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