stm32f103c8t6怎么用标准库定时器1通道1输出PWM波
时间: 2023-09-14 12:03:57 浏览: 45
使用标准库输出PWM波可以分为以下步骤:
1. 配置定时器1的时钟源和预分频器,设置计数器的自动重载值,以及通道1的PWM模式。
```c
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_TimeBaseInitStructure.TIM_Period = 999; // 定时器自动重载值
TIM_TimeBaseInitStructure.TIM_Prescaler = 71; // 预分频器
TIM_TimeBaseInitStructure.TIM_ClockDivision = 0;
TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseInitStructure);
TIM_Cmd(TIM1, ENABLE);
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; // PWM模式下,通道1设置为高电平
TIM_OCInitStructure.TIM_Pulse = 500; // 初始占空比为50%
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
```
2. 在主函数中使用TIM_SetCompare1函数来设置通道1的占空比。
```c
while(1) {
for (uint16_t i = 0; i < 1000; i++) {
TIM_SetCompare1(TIM1, i); // 设置占空比
delay_ms(1); // 延时1ms
}
}
```
完整代码示例:
```c
#include "stm32f10x.h"
void delay_ms(uint16_t ms)
{
while(ms--)
{
volatile uint32_t x=1000;
while(x--);
}
}
int main(void)
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_TimeBaseInitStructure.TIM_Period = 999;
TIM_TimeBaseInitStructure.TIM_Prescaler = 71;
TIM_TimeBaseInitStructure.TIM_ClockDivision = 0;
TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseInitStructure);
TIM_Cmd(TIM1, ENABLE);
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OCInitStructure.TIM_Pulse = 500;
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);
while(1) {
for (uint16_t i = 0; i < 1000; i++) {
TIM_SetCompare1(TIM1, i);
delay_ms(1);
}
}
}
```
注意:该示例代码中使用的占空比范围是0~999,可以根据自己的需求进行修改。同时,定时器时钟频率为1MHz,因此在计算占空比时要注意。例如,占空比为50%时,需要将占空比设置为500。