飞思卡尔串口相关函数

//串口的初始化

//波特率为9600,8位数据格式,无校验,一个停止位,用查询方式发送
void SCI_Init(void) 
{
   SCI0BDH = 0x00;
   SCI0BDL = 0x41;  //波特率=BUSCLK/(16*BR[12:0])=38400 , BUSCLK=40MHz  14400_0xae   38400_0x41  230400_0x0b
   SCI0CR2 = 0x2C; //发送,接收允许,接收采用中断方式
}

 

//将8位二进制数转换为相应的ASCII字符
unsigned char Digit_ASCII(unsigned char temp) 
{
    if(temp>=0x0A)//如查temp有两位,如11,则转换为B
        temp = temp + 'A' - 0x0A;//'A'=65, 0x0A=10,
    else
        temp = temp + '0';     //temp为数字0~9, 只有1位
    return temp;
}

//发送单个字符,下面这两个函数均可以
void SCI_SendChar(unsigned char ch) 
{
   while(SCI0SR1_TC == 0);       //keep waiting when not empty  
   SCI0DRL = ch;
}

//或者
void SCI_SendChar(unsigned char ch) 
{
   while(SCI0SR1_TDRE == 0);       //keep waiting when not empty  
   SCI0DRL = ch;
}

 

//通过SCI发送字符串
void SCI_SendStr(char *str) 
{
    while(*str!=0) 
       SCI_SendChar(*str++); 
}
   
//把一个8位数以ASCII形式通过SCI0发送去
void SCI_SendHex8(unsigned char a) 
{
   unsigned char b;
   b = (unsigned char)(a/0x10);//取8位数的高4位,低估位为0,如0xf1/0x10 = 0xf0
   b = Digit_ASCII(b);
   SCI_SendChar(b);
   b = (unsigned char)(a%0x10);//取8位数的低4位,高4位为0, 如0xf1%0x10 = 0x01;
   b = Digit_ASCII(b);
   SCI_SendChar(b);  
}

//把一个8位无符号数以十进制的形式发送出去  
 void SCI_SendDec8u(unsigned char a) 
 {
    unsigned char b;
    b = (unsigned char)(a/100);//取百位
    b = b + '0';
    SCI_SendChar(b);
    a = a%100;
    b = (unsigned char)(a/10);//取十位
    b = b + '0';
    SCI_SendChar(b);
    b = (unsigned char)(a%10);//取个位
    b = b + '0';
    SCI_SendChar(b);
 }
//将一个16位数以ASCII形式发送出去
void SCI_SendHex16(unsigned int a) 
{
    SCI_SendHex8((unsigned char)(a>>8));//即temp = a>>8; 先传a的高8位
    SCI_SendHex8((unsigned char)a); //后传a的低8位,(一个16位的数赋值给一个8位的变量,只取低8位,高8位自动丢失)
}

//以十进制的形式发送一个16位有符号数
void SCI_SendDec16s(int a) 
{
    unsigned char b;
    if(a&0x8000)//a为负数 
    {
      SCI_SendChar('-');
      a = ~a +1; //取绝对值
    }
    b = (unsigned char)(a/10000);//取万位
    b = b + '0';
    SCI_SendChar(b);
    a = a%10000;
    b = (unsigned char)(a/1000);//取千位
    b = b + '0';
    SCI_SendChar(b);
    a = a%1000;
    b = (unsigned char)(a/100);//取百位
    b = b + '0';
    SCI_SendChar(b);
    a = a%100;
    b = (unsigned char)(a/10);//取十位
    b = b + '0';
    SCI_SendChar(b);
    b = (unsigned char)(a%10);//取个位
    b = b + '0';
    SCI_SendChar(b);
}

//以十进制的形式发送一个16位无符号数
void SCI_SendDec16u(unsigned int a) 
{
    unsigned char b;
    b = (unsigned char)(a/10000);//取万位
    b = b + '0';
    SCI_SendChar(b);
    a = a%10000;
    b = (unsigned char)(a/1000);//取千位
    b = b + '0';
    SCI_SendChar(b);
    a = a%1000;
    b = (unsigned char)(a/100);//取百位
    b = b + '0';
    SCI_SendChar(b);
    a = a%100;
    b = (unsigned char)(a/10);//取十位
    b = b + '0';
    SCI_SendChar(b);
    b = (unsigned char)(a%10);//取个位
    b = b + '0';
    SCI_SendChar(b);
}

 

//接收字符中断服务程序

char data;
#pragma CODE_SEG __NEAR_SEG NON_BANKED
void interrupt 20 SCI0_Interrupt(void) 
{
    if(SCI0SR1_RDRF == 1)//如果是接收到了字符
    {
        SCI0DRL;//清除RDRF的标志位
        data=SCI0DRL;//读取接收到的字符到data中
    }
}