SCI查询方式

                       281x-SCI和PC间的通讯

// $          Date:   30/11/2009        整理：  eyes417      $
//###########################################################################
//

//   FILE :  281x-SCI_PC.c

//
//  TITLE:  281x-SCI和PC间的通讯  ---  查询方式，使用FIFO               

//               PC发送至串口，DSP再回送至PC                                //

//

//                        ASSUMPTIONS:
//   
//   As supplied, this project is configured for "boot to H0" operation.
//   Other then boot mode pin configuration, no other hardware configuration is required. 

//
//###########################################################################

 

# include "DSP281x_Device.h"    // DSP281x Headerfile Include File
# include "DSP281x_Examples.h"   // DSP281x Examples Include File

 void scia_echoback_init(void);
 void scia_fifo_init(void);
 void scia_xmit(int a);                    //串口发送--数据
 void scia_msg(char *msg);                 //串口发送--字符串

 Uint16 LoopCount;

 void main(void)
 {

    Uint16 ReceivedChar;
    char *msg;

// Step 1. Initialize System Control:

    InitSysCtrl();

// Step 2. Initalize GPIO:
 // InitGpio();  //配置IO口功能为SCIA和SCIB模式

    EALLOW;
    GpioMuxRegs.GPFMUX.bit.SCITXDA_GPIOF4 = 1;
    GpioMuxRegs.GPFMUX.bit.SCIRXDA_GPIOF5 = 1;
    GpioMuxRegs.GPGMUX.bit.SCITXDB_GPIOG4 = 1;
    GpioMuxRegs.GPGMUX.bit.SCIRXDB_GPIOG5 = 1;
    EDIS;

// Step 3. Clear all interrupts and initialize PIE vector table:

    DINT;                   // Disable CPU interrupts
        
    InitPieCtrl();         //初始化PIE控制寄存器

    IER = 0x0000;               

    IFR = 0x0000;

    InitPieVectTable();    //初始化PIE中断向量表

// Step 4. Initialize all the Device Peripherals:

   // InitPeripherals();    //初始化所有外设

// Step 5. User specific code:

    scia_fifo_init();      

    scia_echoback_init(); 

//从PC上的串口调试助手输入要发送的数据至DSP

    msg = "/r/nYou will enter a character, and the DSP will echo it back! /n/0";
    scia_msg(msg);

    for(;;)
    {
       msg = "/r/nEnter a character: /0";
       scia_msg(msg);

       // 查询方式--接收--使用FIFO
       while(SciaRegs.SCIFFRX.bit.RXFIFST!=1) { }      // wait for XRDY =1 for empty state
                                                       //XRDY =1 (空状态)等待数据发送
       // 接收数据
       ReceivedChar = SciaRegs.SCIRXBUF.all;

       // Echo character back
       msg = "  You sent: /0";
       scia_msg(msg);
       scia_xmit(ReceivedChar);     //串口发送函数

       LoopCount++;

     }  //end for

}  //end main

 

//SCI-A初始化
void scia_echoback_init()
{
//通信控制寄存器,1个停止位,无奇偶校验,自测试禁止,空闲线模式,字符长度8位 
  SciaRegs.SCICCR.all =0x0007;  

//禁止接收错误中断,禁止休眠,使能发送，接收  
 SciaRegs.SCICTL1.all =0x0003;  
 SciaRegs.SCICTL2.all =0x0003;
 SciaRegs.SCICTL2.bit.TXINTENA =1;   //使能TXRDY中断
 SciaRegs.SCICTL2.bit.RXBKINTENA =1; //接收缓冲器中断使能

//波特率设置 SCI-Band=LSPCLK/((BRR+1)*8)---9600K
 SciaRegs.SCIHBAUD = 0x0001;  
 SciaRegs.SCILBAUD = 0x00E7;

 SciaRegs.SCICTL1.all =0x0023;  // SCI初始化完成退出复位重启状态

}

//串口发送--变量
void scia_xmit(int a)
{
    while (SciaRegs.SCIFFTX.bit.TXFFST != 0) {}
    SciaRegs.SCITXBUF=a;

}

//串口发送--字符或字符串
 void scia_msg(char * msg)
 {
    int16 i;
    i = 0;
    while(msg[i] != '/0')
    {
        scia_xmit(msg[i]);
        i++;
    }
 }

// 初始化 SCI--FIFO
 void scia_fifo_init()
 {
    SciaRegs.SCIFFTX.all=0xE040;  //允许接收，使能FIFO，清除TXFIFINT
    SciaRegs.SCIFFRX.all=0x204f;  //使能FIFO接收，清除RXFFINT,16级FIFO
    SciaRegs.SCIFFCT.all=0x0000;  //禁止波特率校验

 }

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// No more.
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