STM32结合AD1256调试，无法出正常结果

只看该作者 · 2014-12-19 11:11

STM32结合AD1256进行调试，始终不能出正常结果，不知道有没有大神调过，能否帮我看下程序，我可能没有分数，初来这个论坛，还望大神给予指导。
示波器显示波形也正确，无论模拟输入多少，输出变量值始终为0x10453附近变动，请教各位大神，有了解的吗？
以下是程序：
int main(void)
{
// unsigned long results = 0;
unsigned char i = 0;
SystemInit();                      //时钟初始化
delay_init(72);                      //延迟初始化
SPI_ADS1256_Init();    //SPI初始化
ADS1256_GPIO_init();    //与AD相关GPIO初始化
ADS1256_Init();//AD1256初始化
while(1)
{
results = ADS1256ReadData();
}
以下SPI_ADS1256_Init()-----------------------------------
void SPI_ADS1256_Init(void)
{
  SPI_InitTypeDef  SPI_InitStructure;
  GPIO_InitTypeDef GPIO_InitStructure;
  /* Enable SPI1 and GPIO clocks */
  /*!< SPI_FLASH_SPI_CS_GPIO, SPI_FLASH_SPI_MOSI_GPIO,
   SPI_FLASH_SPI_MISO_GPIO, SPI_FLASH_SPI_DETECT_GPIO
   and SPI_FLASH_SPI_SCK_GPIO Periph clock enable */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOD, ENABLE);
/*!< SPI_FLASH_SPI Periph clock enable */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
  /*!< AFIO Periph clock enable */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
  /*!< Configure SPI_FLASH_SPI pins: SCK */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;                     //
// GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; // ÍÆÃâÊä³ö
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  // ¸´ÓÃÍÆÃâÊä³ö
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
  /*!< Configure SPI_FLASH_SPI pins: DIN */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;                   //
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; // ¸´ÓÃÍÆÃâÊä³ö
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
  /*!< Configure SPI_FLASH_SPI pins: DOUT */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;                     //
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; //ÉÏÀÊäÈë
// GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; // ¸´ÓÃÍÆÃâÊä³ö
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex
  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
  SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;    //
  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;    //´
  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_64;
  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;    //Êý¾Ý´«Êä´ÓMSBÎ»¿ªÊ¼
  SPI_InitStructure.SPI_CRCPolynomial = 7;    //CRCÖµ¼ÆËãµÄ¶àÏîÊ½
  SPI_Init(SPI1, &SPI_InitStructure);
/* Enable SPI1  */
  SPI_Cmd(SPI1, ENABLE);
}

void ADS1256_GPIO_init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/////////CS  reset Òý½ÅÉèÖÃ
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Pin= GPIO_Pin_4 | GPIO_Pin_12;
GPIO_InitStructure.GPIO_Mode= GPIO_Mode_Out_PP; //--ÍÆÃâÊä³öÄ£Ê½
//GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed= GPIO_Speed_10MHz; //--GPIO·×ªËÙ¶ÈÎª50MHz

GPIO_Init(GPIOA , &GPIO_InitStructure); //--½«ÅäÖÃÐ´Èë¶ÔÓ¦µÄGPIO¼Ä´æÆ÷ÖÐ

// GPIO_InitTypeDef GPIO_InitStructure;
///////// DRDYÒý½ÅÉèÖÃ
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Pin= GPIO_Pin_2;
GPIO_InitStructure.GPIO_Mode= GPIO_Mode_IN_FLOATING; //--¸¡µãÊäÈëÄ£Ê½
GPIO_InitStructure.GPIO_Speed= GPIO_Speed_10MHz; //--GPIO·×ªËÙ¶ÈÎª50MHz
GPIO_Init(GPIOA , &GPIO_InitStructure); //--½«ÅäÖÃÐ´Èë¶ÔÓ¦µÄGPIO¼Ä´æÆ÷ÖÐ

GPIO_Init(GPIOA , &GPIO_InitStructure); //--½«ÅäÖÃÐ´Èë¶ÔÓ¦µÄGPIO¼Ä´æÆ÷ÖÐ
}

void ADS1256_Init(void)
{
ADS_CS_LOW();
RESET_HIGH();
delay_us(100);
SPI_SendByte(ADS1256_CMD_REST);
delay_ms(10);
while(ADS_DRDY);                               //µ±ADS1256_DRDYÎªµÍÊ±²ÅÄÜÐ´¼Ä´æÆ÷
SPI_SendByte(ADS1256_CMD_SYNC);                //Í¬²½ÃüÁî
SPI_SendByte(ADS1256_CMD_WAKEUP);             //Í¬²½»½ÐÑ

while(ADS_DRDY);
SPI_SendByte(ADS1256_CMD_WREG | ADS1256_STATUS);//Á¬ÐøÐ´Èë4¸ö¼Ä´æÆ÷
SPI_SendByte(3);
SPI_SendByte(0x04);                            //¸ßÎ»ÔÚÇ°£¬Ê¹ÓÃÄÚ²¿Ð£×¼£¬²»Ê¹ÓÃ»º´æ
SPI_SendByte(ADS1256_MUXP_AIN2 | ADS1256_MUXN_AIN3);//¶Ë¿ÚÊäÈëA2ÎªÕý£¬A3Î»¸º
SPI_SendByte(ADS1256_GAIN_1);                //·Å´ó±¶ÊýÉèÖÃ
SPI_SendByte(ADS1256_DRATE_2_5SPS);          //²É¼¯ËÙ¶ÈÉèÖÃ
delay_us(100);

while(ADS_DRDY);                               //µ±ADS1256_DRDYÎªµÍÊ±²ÅÄÜÐ´¼Ä´æÆ÷
SPI_SendByte(ADS1256_CMD_SELFCAL);             //Æ«ÒÆºÍÔöÒæ×Ô¶¯Ð£×¼

ADS_CS_HIGH();
delay_ms(100);

}

unsigned long ADS1256ReadData(void)
{
unsigned char i=0;
unsigned long sum=0;
unsigned long r=0;
ADS_CS_LOW();

while(ADS_DRDY);             //µ±ADS1256_DRDYÎªµÍÊ±²ÅÄÜÐ´¼Ä´æÆ÷
SPI_SendByte(ADS1256_CMD_SYNC);
SPI_SendByte(ADS1256_CMD_WAKEUP);
SPI_SendByte(ADS1256_CMD_RDATA);
delay_us(10);                //min=50*(1/fCLKIN)=50*(1/7.68MHZ)=6500ns;max=whatever
for(i=0;i<3;i++)
{
sum = sum << 8;
r = SPI_SendByte(0);
      sum |= r;
}
ADS_CS_HIGH();
return sum;
}