我和一个按键/LED控制IC=BC7277进行SPI0控制.结果发现

1:由于BC7277工作在64KHZ以下.我对SPI0_BAND=0X0320

2:我检测SPI0_SCK,发现上电复位波形是12.5M的脉冲,但是我初始化SPI后,波形基本没变化,并没有达到我想的64K以下.

3:我测试SPI0_MISO和SPI0_MOSI,都没测到信号,全是不稳定的高电平.

4:F10运行,发现控制有效,能发送数据,但是是错误的.能接受数据,但是也是错误的.--由于示波器无法检测,不知道问题在哪儿.

5:代码如下

Set_PLL(16,4);

Init_Bc7277_Ports();

SPI0_init();

while(1)
          {
            keydata=Bc7277_SPI0_rw(0x1d,0xff);}

void Init_Bc7277_Ports(void)
{
*pPORTG_FER                   |=PG12|PG13|PG14|PG15;        //PG12-PG15=peripheral function
*pPORTG_MUX                   &=0x3fff;
}

void SPI0_init(void)
{
*pSPI0_BAUD=0x0320;                     //配置速率为1/4系统时钟  SPI速率 = SCLK/2*SPI_BAUD
*pSPI0_FLG |=FLS2;    //选择SPI0SEL2接口
*pSPI0_CTL = 0x1001|CPHA| CPOL|EMISO|GM;  //配置模式为手动片选模式
*pSPI0_CTL = (*pSPI0_CTL | SPE); //使能SPI1接口
}

unsigned int Bc7277_SPI0_rw(unsigned char address,unsigned char data)                        //从SPI中读取数据        
{          
          unsigned int read_bc7277_buf;
unsigned int  i,j;
*pSPI_FLG &=~FLG2;                      //将SPI0SEL2拉到0-----------?在ADS7843.C中不用          
delay(0x0320);
          while(!(*pSPI_STAT&SPIF));              //查看SPI传输状态是否完成          
          *pSPI0_TDBR         =address;                 //将数据传入SPI传输数据寄存器0X55          
          *pSPI0_FLG          |=FLG2;             //-----------?在ADS7843.C中不用
          while(*pSPI_STAT & RXS)                 //查看SPI传输状态是否有数据需要接受
          j                   =*pSPI_RDBR;        //读取数据          
          *pSPI_FLG           |=FLG2;             //将SPI0SEL2拉到1,完成数据传输.-----------?在ADS7843.C中不用
          
          *pSPI_FLG &=~FLG2;                      //将SPI0SEL2拉到0-----------?在ADS7843.C中不用          
          while(!(*pSPI_STAT&SPIF));              //查看SPI传输状态是否完成          
          *pSPI0_TDBR         =data;                 //将数据传入SPI传输数据寄存器0X55          
         *pSPI0_FLG          |=FLG2;             //-----------?在ADS7843.C中不用
          
          *pSPI0_FLG          &=FLG2;             //将SPI0SEL2拉到0-----------?在ADS7843.C中不用
          while(*pSPI_STAT & RXS)                 //查看SPI传输状态是否有数据需要接受
          j                   =*pSPI_RDBR;        //读取数据          
          *pSPI_FLG           |=FLG2;             //将SPI0SEL2拉到1,完成数据传输.-----------?在ADS7843.C中不用
          read_bc7277_buf     =j;                 //格式转换=>read_bc7277_buf=(unsigned char) j;
          return(read_bc7277_buf);
}