为什么我输出的三角波频率不是1khz
#include "stm32f10x.h" // Device header
#include "Delay.h"
void DAC_init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
DAC_InitTypeDef DAC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC,ENABLE );//使能dac时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE );//使能GpioA时钟
//Gpio4为模拟输出
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
DAC_InitStructure.DAC_Trigger = DAC_Trigger_T2_TRGO; // 触发源为TIM2 TRGO
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_Triangle; // 生成三角波
DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_TriangleAmplitude_4095; // 设置振幅为4095
DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable; // 禁用输出缓冲
DAC_Init(DAC_Channel_1, &DAC_InitStructure);
DAC_Cmd(DAC_Channel_1,ENABLE);//使能DAC通道1
// DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);//开启DAC通道1
}
void TIM2_waveInit(uint16_t arr, uint16_t psc)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_TimeBaseStructure.TIM_Period = arr; // 设定计数器自动重装值
TIM_TimeBaseStructure.TIM_Prescaler = psc; // 预分频器
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
// 选择更新事件作为触发输出
TIM_SelectOutputTrigger(TIM2, TIM_TRGOSource_Update);
// 使能定时器2
TIM_Cmd(TIM2, ENABLE);
}
int main(void)
{
TIM2_waveInit(999,71);
DAC_init();
while (1)
{
}
}
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