具体目的

使用STM32的SPI通道，采集ADS8320对DT50（激光测距传感器）进行了AD转换之的数据。不要求进行滤波，但采集到的数据要与距离呈正相关。

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具体代码

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main.h

#ifndef _MAIN_H
#define _MAIN_H
#include "SPI_DMA_Config.h"
#include "stm32f10x.h"
#include "delay_ms.h"

int SPI_Word(u16 word);
#endif

main.c

#include"main.h"
uint16_t Data[10];
uint16_t data=0;
int main()
{
	SystemInit();
	SPI_DMA_Config();
	while(1)
		{

		}

}

SPI_Config.h

#ifndef __SPI_CONFIG
#define __SPI_CONFIG
#include "stm32f10x.h"

void SPI_Config();
int Read_ADC_Value(void);
#endif

SPI_Config.c

#include "SPI_Config.h"
extern uint16_t Data[10];
extern uint16_t data;
void SPI_Config()
{
	GPIO_InitTypeDef GPIO_InitStructure;
	SPI_InitTypeDef SPI_InitStructure;
	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
	NVIC_InitTypeDef NVIC_InitStructure;
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOA , ENABLE );
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2  | RCC_APB1Periph_TIM2, ENABLE );
	
	//ADS8320引脚配置
	/*----SPI_SCLK----PB13----*/         //时钟信号
	/*----SPI_SDO----PB14----*/          //串行输出
	/*----CS/SHDN----PB12----*/          //使能信号
	
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOB, &GPIO_InitStructure);

	
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; 
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; 
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;	
	GPIO_Init(GPIOA, &GPIO_InitStructure);
	
	//SPI配置
	SPI_Cmd(SPI2, DISABLE);
	SPI_InitStructure.SPI_Direction =SPI_Direction_2Lines_FullDuplex;
	SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
	SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;
	SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
	SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
	SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
	SPI_InitStructure.SPI_BaudRatePrescaler =SPI_BaudRatePrescaler_32;
	SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
	SPI_InitStructure.SPI_CRCPolynomial = 7;
	SPI_Init(SPI2, &SPI_InitStructure);
	SPI_Cmd(SPI2, ENABLE);
	
	NVIC_InitStructure.NVIC_IRQChannel =TIM2_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ; 
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; 
	NVIC_Init(&NVIC_InitStructure);

	TIM_TimeBaseStructure.TIM_Period = 1250-1;
	TIM_TimeBaseStructure.TIM_Prescaler = 144-1;
	TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
	TIM_TimeBaseInit(TIM2,&TIM_TimeBaseStructure);
	
	TIM_Cmd(TIM2, ENABLE);	 
    TIM_ITConfig(TIM2, TIM_IT_Update,ENABLE);            //打开TIM2中断
    TIM_ClearFlag(TIM2, TIM_FLAG_Update);
}

//SPI接收采集数据，全双工模式下，发送一次，采集一次
int SPI_Word(u16 word)      
{
	while(SPI_I2S_GetFlagStatus(SPI2,SPI_I2S_FLAG_TXE)==RESET);
	SPI_I2S_SendData(SPI2,word);
	while(SPI_I2S_GetFlagStatus(SPI2,SPI_I2S_FLAG_RXNE)==RESET);
	return SPI_I2S_ReceiveData(SPI2);
}

int Read_ADC_Value(void)
{
	int ADC_value=0;
	
  GPIO_ResetBits(GPIOB,GPIO_Pin_12);//片选信号，低电平触发，ADS8320进行一次数据采集
	ADC_value=SPI_Word(0x0000);
	GPIO_SetBits(GPIOB,GPIO_Pin_12);//关闭片选，屏蔽从低到高位数据，只采集，从高位到地位数据
	return ADC_value;   //返回采样值
}

//利用定时器中断进行数据采集，确定每次采集的间隔时间
void TIM2_IRQHandler(void)
{
  if (TIM_GetITStatus(TIM2,TIM_IT_Update)!= RESET)         
	{
                                              
    TIM_ClearFlag(TIM2, TIM_FLAG_Update);	
				Data[data]=Read_ADC_Value();
				data++;
			if(data>9)
				data=0;

  }
}