我看资料是PA.4为DAC输出口,将例程写入后,用万用表一个点到VREF-,一个点到29脚,如果有正弦波输出,电压值应该是不停变化,但是现在是只有一个1.6V的稳定电压,求高手看看哪里出错了。板是大虾DX32。
/******************** (C) COPYRIGHT 2008 STMicroelectronics ********************
* File Name : main.c
* Author : MCD Application Team
* Version : V2.0
* Date : 05/23/2008
* Description : Main program body.
********************************************************************************
* THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME.
* AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT,
* INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE
* CONTENT OF SUCH SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING
* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
* FOR MORE INFORMATION PLEASE CAREFULLY READ THE LICENSE AGREEMENT FILE LOCATED
* IN THE ROOT DIRECTORY OF THIS FIRMWARE PACKAGE.
*******************************************************************************/
/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define DAC_DHR12RD_Address 0x40007420
/* Init Structure definition */
DAC_InitTypeDef DAC_InitStructure;
DMA_InitTypeDef DMA_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
ErrorStatus HSEStartUpStatus;
uc16 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};
u32 DualSine12bit[32];
u8 Idx = 0;
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void GPIO_Configuration(void);
void NVIC_Configuration(void);
void Delay(vu32 nCount);
/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name : main
* Description : Main program.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
int main(void)
{
#ifdef DEBUG
debug();
#endif
/* System Clocks Configuration */
RCC_Configuration();
/* GPIO configuration */
GPIO_Configuration();
/* NVIC Configuration */
NVIC_Configuration();
/* TIM8 Configuration */
/* Time base configuration */
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);
/* TIM8 TRGO selection */
TIM_SelectOutputTrigger(TIM8, TIM_TRGOSource_Update);
/* DAC channel1 Configuration */
DAC_StructInit(&DAC_InitStructure);
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 channel2 Configuration */
DAC_Init(DAC_Channel_2, &DAC_InitStructure);
/* Fill Sine32bit table */
for (Idx= 0; Idx<32; Idx++)
{
DualSine12bit[Idx] = (Sine12bit[Idx] << 16) + (Sine12bit[Idx]);
}
/* DMA2 channel4 configuration */
DMA_DeInit(DMA2_Channel4);
DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR12RD_Address;
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&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);
/* Enable DMA2 Channel4 */
DMA_Cmd(DMA2_Channel4, ENABLE);
/* Enable DAC Channel1 */
DAC_Cmd(DAC_Channel_1, ENABLE);
/* Enable DAC Channel2 */
DAC_Cmd(DAC_Channel_2, ENABLE);
/* Enable DMA for DAC Channel2 */
DAC_DMACmd(DAC_Channel_2, ENABLE);
/* TIM8 enable counter */
TIM_Cmd(TIM8, ENABLE);
while (1)
{
}
}
/*******************************************************************************
* Function Name : RCC_Configuration
* Description : Configures the different system clocks.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void RCC_Configuration(void)
{
/* RCC system reset(for debug purpose) */
RCC_DeInit();
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);
/* Wait till HSE is ready */
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if(HSEStartUpStatus == SUCCESS)
{
/* Enable Prefetch Buffer */
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* Flash 2 wait state */
FLASH_SetLatency(FLASH_Latency_2);
/* HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
/* PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1);
/* PCLK1 = HCLK/2 */
RCC_PCLK1Config(RCC_HCLK_Div2);
/* PLLCLK = 8MHz * 9 = 72 MHz */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);
/* Enable PLL */
RCC_PLLCmd(ENABLE);
/* Wait till PLL is ready */
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
{
}
/* Select PLL as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* Wait till PLL is used as system clock source */
while(RCC_GetSYSCLKSource() != 0x08)
{
}
}
/* Enable peripheral clocks --------------------------------------------------*/
/* DMA clock enable */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA2, ENABLE);
/* AFIO and GPIOA Periph clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO | RCC_APB2Periph_GPIOA, ENABLE);
/* DAC Periph clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
/* TIM8 Periph clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);
}
/*******************************************************************************
* Function Name : GPIO_Configuration
* Description : Configures the different GPIO ports.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* Configure DAC channe1 and DAC channel2 outputs pins */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
}
/*******************************************************************************
* Function Name : NVIC_Configuration
* Description : Configures Vector Table base location.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void NVIC_Configuration(void)
{
#ifdef VECT_TAB_RAM
/* Set the Vector Table base location at 0x20000000 */
NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else /* VECT_TAB_FLASH */
/* Set the Vector Table base location at 0x08000000 */
NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif
}
/*******************************************************************************
* Function Name : Delay
* Description : Inserts a delay time.
* Input : nCount: specifies the delay time length.
* Output : None
* Return : None
*******************************************************************************/
void Delay(vu32 nCount)
{
for(; nCount != 0; nCount--);
}
#ifdef DEBUG
/*******************************************************************************
* Function Name : assert_failed
* Description : Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* Input : - file: pointer to the source file name
* - line: assert_param error line source number
* Output : None
* Return : None
*******************************************************************************/
void assert_failed(u8* file, u32 line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* Infinite loop */
while (1)
{
}
}
#endif
/******************* (C) COPYRIGHT 2008 STMicroelectronics *****END OF FILE****/ |
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