【IoT】蓝牙BLE基础：CC254x通信系列之模拟SPI协议

CC254x 模拟 SPI：

1、宏定义：

      #define SPI_CS                          P1_4
      #define SPI_CLK                         P1_5
      #define SPI_MOSI                        P1_7
      #define SPI_MISO                        P1_6
  
 

2、引脚配置

      void SPI_Init(void)
      {
          P1SEL &= 0x0F; //将 P1.4 P1.5 P1.6 P1.7 设置为GPIO引脚          00001111
          P1DIR |= 0xB0; //设置 P1.4 P1.5, p1.7 引脚为输出, P1.6为输入    10110000
      }
  
 

3、读字节函数

      uint8 SPI_ReadByte(void)
      {
          unsigned char i=0, in=0, temp=0;
          //先拉低, 然后拉高的时候, 读取MISO
          SPI_CLK = 0;
          for(i=0;i<8;i++){
              in = (in << 1);
              SPI_CLK = 1;
              //SPI_DLY_us(1);
              temp = SPI_MISO;
              if (temp == 1){
                  in = in | 0x01;
              }
              SPI_CLK = 0;
              //SPI_DLY_us(1);
          }
          return in;
      }
  
 

4、写字节函数

      void SPI_SendByte(uint8 cmd)
      {
          unsigned char i=8, temp=0;
          //SPI_CS=0;
          for(i=0;i<8;i++){
              SPI_CLK=0;
              temp = cmd&0x80;
              if (temp == 0)
              {
                  SPI_MOSI = 0;
              }
              else
              {
                  SPI_MOSI = 1;
              }
              cmd<<=1;;
              SPI_CLK=1;
              //SPI_DLY_us(1);
          }
          SPI_MOSI=1;
      }
  
 

5、读数据

      unsigned char ReadRawRC(unsigned char Address)
      {
        unsigned char ucAddr, ucResult=0;
        SPI_CS=0;
        ucAddr = ((Address<<1)&0x7E)|0x80;
        SPI_SendByte(ucAddr);
        ucResult = SPI_ReadByte();
        SPI_CS = 1;
        return ucResult;
      }
  
 

6、写数据

      void WriteRawRC(unsigned char Address, unsigned char value)
      {
        unsigned char  ucAddr;
        SPI_CS=0;
        ucAddr = ((Address<<1)&0x7E);
        SPI_SendByte(ucAddr);
        SPI_SendByte(value);
        SPI_CS = 1;
      }
  
 

文章来源: blog.csdn.net，作者：简一商业，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/liwei16611/article/details/73420685