test8.c

5402开发板附带的源程序

#include "REG5402.h"

int timer1_over;

int serial_temp;    
int a1;
int a2;

int serialbyte_receive()
{
   unsigned int i,a;

   a=0;
   
   for(;RXD!=0;);

   PRD1=0xef;
   TCR1=0x02eb;
   while(timer1_over==0);
   timer1_over=0;
  
   if(RXD==0)
   {
      for(i=0;i<8;i++)
      {
         PRD1=0x1df;   
         TCR1=0x02eb;
         for(;timer1_over==0;);
         timer1_over=0;

         a=a>>1;
         if(RXD!=0)
            a=a|0x8000;
      }

      PRD1=0x1df;
      TCR1=0x02eb;
      for(;timer1_over==0;);
      timer1_over=0;

      if(RXD==0) return 0;
   }

   else return 0;
   a=a>>8;
   serial_temp=a;        
   return 1;
}
void cpu_init()
{
  
   PMST=0x3fa0;      
   SWWSR=0x7fff;
   SWCR=0x0000;
   IMR=0; IFR=IFR;

   SPSA1=0xe;        
   SPSD1=0x3020;     
}

void timer1_init()       /* Sample time */
{
   PRD1=0x1df;      
   TCR1=0x039b;     
                     
   IMR=IMR|0x0080;
}


main()
{
   int i;
   serial_temp=0;  
   
   asm(" ssbx intm");
   cpu_init();
   timer1_init();
   asm(" rsbx intm");
   
   for(;;)
   {     
      i=serialbyte_receive();
      if(serial_temp==0xff)
      {
         i=serialbyte_receive();
         a1=serial_temp;
         i=serialbyte_receive();
         a2=serial_temp;
         READS=(a1<<8)+a2;
       }
   }
}

interrupt void timer1_int()
{
   timer1_over=1;
   TCR1=0x039b;
}