- include<reg51.h>
- define Motors P2
- define Switches P1
- define Forward 0x05
- define Backward 0x0a
- define Left 0x06
- define Right 0x09
- define stop 0x00void
main() { unsigned char SwitchInput; Switches = 0x0f; //Configure Switches as Input Motors = 0X00; //Configure both Motors as Output. while(1)
{	  
SwitchInput = (0x0f & Switches)//read switch status and mask lower byte.     
switch(SwitchInput)	
{
       case 1: Motors = Forward; break;	 
       case 2: Motors = Backward; break;	  
       case 4: Motors = Left; break;	  
       case 8: Motors = Right; break;	  
       default: Motors =stop;	 
       }   
}
}
