#include "stm32f10x.h"
void PWM_Config(void) {
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
// 配置定时器基础参数,PWM频率 = 72MHz / (7200*10) = 1kHz
TIM_TimeBaseStructure.TIM_Period = 9; // 自动重装载值
TIM_TimeBaseStructure.TIM_Prescaler = 7199; // 预分频器
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
// 配置PWM模式
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 4; // 占空比50%
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OC1Init(TIM3, &TIM_OCInitStructure);
// 使能定时器更新事件作为触发源
TIM_SelectOutputTrigger(TIM3, TIM_TRGOSource_Update);
TIM_Cmd(TIM3, ENABLE);
}
void ADC_Config(void) {
ADC_InitTypeDef ADC_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_GPIOA, ENABLE);
// 配置ADC输入引脚 PA0
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
// ADC配置
ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_InitStructure.ADC_ScanConvMode = DISABLE;
ADC_InitStructure.ADC_ContinuousConvMode = DISABLE; // 单次转换模式
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T3_TRGO; // 定时器3触发
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfChannel = 1;
ADC_Init(ADC1, &ADC_InitStructure);
// 配置通道0,采样时间55.5周期
ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_55Cycles5);
// 使能外部触发转换
ADC_ExternalTrigConvCmd(ADC1, ENABLE);
ADC_Cmd(ADC1, ENABLE);
// ADC校准
ADC_ResetCalibration(ADC1);
while(ADC_GetResetCalibrationStatus(ADC1));
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1));
}
uint16_t Get_ADC_Value(void) {
// 等待转换完成
while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC));
return ADC_GetConversionValue(ADC1);
}
int main(void) {
PWM_Config(); // 配置PWM触发源
ADC_Config(); // 配置ADC为外部触发模式
uint16_t adc_value;
while(1) {
adc_value = Get_ADC_Value(); // 获取PWM触发后的采样值
// 处理采样数据...
}
}
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