8051之串列中斷

設定8051串列中斷,並開啟Time0計時中斷

//設定中斷模式
void init_rs232(void)
{
 IE=0x9A;              //開啟time0計時中斷 time1串列中斷 關閉外部中斷
                               // ES=1;   EA=1;  ET0=1;          ET1=1;
 IP=0x02;               //設定time0計時中斷 權限 高於time1串列中斷
 TMOD = 0x21;     //time0 mode1  time1 mode2
 SCON = 0x50;     //設定模式 串列中斷mode1 鮑率可變 REN=1   RI = 0;  TI = 0;
 PCON = 0x00;     //清除SMOD
 TH1 = 253;          //設定鮑率為9600    11.059MHz
 TR1 = 1;              //啟動time1產生鮑率
}


//RX接收副程式
char UART_RxChar()
{
  while(RI==0);   // Wait till the data is received
  RI=0;        // Clear Receive Interrupt Flag for next cycle
  return SBUF;   // return the received char
}


//TX傳輸副程式
 void UART_TxChar(char ch)
{
    SBUF=ch;    // Load the data to be transmitted
  while(TI==0);    // Wait till the data is trasmitted
     TI=0;     //Clear the flag for next cycle.
}