F303硬件SPI驱动XPT2046读取数据为0，请教各位大神

eurphan 提问时间：2015-12-27 12:26 /

问答
是否解决:

读取数据全为0，折腾了两天了，麻烦各位大神帮忙看看，万分感谢

void Touch_Init(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
EXTI_InitTypeDef EXTI_InitStructure;
SPI_InitTypeDef SPI_InitStructure;

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOC , ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI3, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;//ÉÏÀÍìÍÆÊä³ö
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOC, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9|GPIO_Pin_11|GPIO_Pin_12|GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF ;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN;
GPIO_Init(GPIOC, &GPIO_InitStructure);

SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOC, EXTI_PinSource9);
EXTI_InitStructure.EXTI_Line = EXTI_Line9;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);

GPIO_PinAFConfig (GPIOC, GPIO_Pin_11|GPIO_Pin_12|GPIO_Pin_10, GPIO_AF_6);
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_256;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge ;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_Init(SPI3,&SPI_InitStructure);
SPI_Cmd(SPI3, ENABLE);

NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

}

u16 Read_AD(u8 CMD)
{
u16 num=0,num1=0;
TCS_ON;
delay_us(10);
//while (SPI_I2S_GetFlagStatus(SPI3, SPI_I2S_FLAG_TXE) == RESET);
SPI_SendData8(SPI3,CMD);//·¢ËÍÃüÁî×Ö
delay_us(10);
//while (SPI_I2S_GetFlagStatus(SPI3, SPI_I2S_FLAG_RXNE) == RESET);
num=SPI_ReceiveData8(SPI3);
num1=SPI_ReceiveData8(SPI3);
TCS_OFF;
num<<=8;
num|=num1;
num>>=3;
num&=0xfff;
return(num);
}