?原子哥，用DMA+DAC生成正弦波，DAC通道1,2传输的问题

南方的狼 · 发表于 2014-9-28 15:26:16

#include "stm32f10x.h"
#define DAC_DHR12RD_Address 0x40007420
DAC_InitTypeDef DAC_InitStructure;
DMA_InitTypeDef DMA_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
const uint16_t Sine12bit[32] = {2047, 2447, 2831, 3185, 3498, 3750, 3939, 4056, 4095, 4056,
3939, 3750, 3495, 3185, 2831, 2447, 2047, 1647, 1263, 909,
599, 344, 155, 38, 0, 38, 155, 344, 599, 909, 1263, 1647};
uint32_t DualSine12bit[32];
uint8_t Idx = 0;
void RCC1_Configuration(void)
{
SystemInit();
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA2, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);
}
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
}
void Timer8_Configuration(void)
{
TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
TIM_TimeBaseStructure.TIM_Period =0x19;
TIM_TimeBaseStructure.TIM_Prescaler = 0x0;
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);
TIM_SelectOutputTrigger(TIM8, TIM_TRGOSource_Update);
TIM_Cmd(TIM8, ENABLE);
}
void DAC_Configuration(void)
{
DAC_InitStructure.DAC_Trigger = DAC_Trigger_T8_TRGO;
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;
DAC_Init(DAC_Channel_1, &DAC_InitStructure);
DAC_Init(DAC_Channel_2, &DAC_InitStructure);
DAC_Cmd(DAC_Channel_1, ENABLE);
DAC_Cmd(DAC_Channel_2, ENABLE);
DAC_DMACmd(DAC_Channel_2, ENABLE);
}
void DMA_Configuration(void)
{
DMA_DeInit(DMA2_Channel4);
DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR12RD_Address;
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&DualSine12bit;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStructure.DMA_BufferSize = 32;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA2_Channel4, &DMA_InitStructure);
DMA_Cmd(DMA2_Channel4, ENABLE);
}
int main(void)
{
RCC1_Configuration();
GPIO_Configuration();
Timer8_Configuration();
DAC_Configuration() ;
DMA_Configuration();
for (Idx= 0; Idx<32; Idx++)
{
DualSine12bit[Idx] = (Sine12bit[Idx] << 16) + (Sine12bit[Idx]);
}
while(1)
{
}
}
原子哥，这段是用DMA+DAC生成正弦波的程序，但此DMA传输只是针对DMA2_Channel4也就是DAC通道2的，为什么DAC通道1也能输出正弦波？