STM32429的DAC

只看该作者 · 2018-10-10 12:50

各位同学好，这两天弄STM32的DAC,发现输出不了可变电压。我是看了手册，之后借鉴了一下开发板的教程，但是没有完全依照教程来做。因为按到手册里面有说，如果不设置TEN, 那么，在写入到：
0: DAC channel1 trigger disabled and data written into the DAC_DHRx register are
transferred one APB1 clock cycle later to the DAC_DOR1 register

我想，那就不用触发模式。直接写入数据寄存器，让它自己动去转换成模拟电压。

下面是我的程序，请帮忙看看，是啥问题，多谢！
void Init_DAC(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
DAC_InitTypeDef DAC_InitStructure;

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE);

GPIO_InitStructure.GPIO_Pin =GPIO_Pin_5;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_Init(GPIOA, &GPIO_InitStructure);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);

DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_TriangleAmplitude_4095;

DAC_Init(DAC_Channel_2, &DAC_InitStructure);

DAC_Cmd(DAC_Channel_2,ENABLE);

}

void Feed_DAC(unsigned int val)
{
if(val>4096)
val=4096;

DAC_SetChannel2Data(DAC_Align_12b_R,val);
}
在Main函数里，先调用Init_DAC,然后调用Feed_DAC(4096);

只看该作者 · 2018-10-10 12:51

Bit 2 TEN1: DAC channel1 trigger enable
This bit is set and cleared by software to enable/disable DAC channel1 trigger.
0: DAC channel1 trigger disabled and data written into the DAC_DHRx register are
transferred one APB1 clock cycle later to the DAC_DOR1 register
1: DAC channel1 trigger enabled and data from the DAC_DHRx register are transferred
three APB1 clock cycles later to the DAC_DOR1 register
Note: When software trigger is selected, the transfer from the DAC_DHRx register to the
DAC_DOR1 register takes only one APB1 clock cycle.

1万 · 2018-10-10 14:36

我的怎么没有你的这么麻烦啊

STM32429的DAC

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