openMSP430之io_test

 

openMSP430:　IO functionality test with interupt

#include "omsp_system.h"



volatile char shift = 0x01;  // Global variable

 

int main(void) 
{



    WDTCTL = WDTPW | WDTHOLD;          // Disable watchdog timer



    P2DIR  = 0xff;                     // Port 2.0-2.7 = output

    P2OUT  = shift;　　　　　　          // Initialize Port 2



    P1DIR  = 0x00;                     // Port 1.0-1.7 = input

    P1IE   = 0x01;                     // Port 1.0 interrupt enabled

    P1IES  = 0x00;                     // Port 1.0 interrupt edge selection (0=pos 1=neg)

    P1IFG  = 0x00;                     // Clear all Port 1 interrupt flags (just in case)

   

    eint();                            // Enable interrupts

 

    while (1) 
　　{

      if (P2OUT == 0x00)
　　   {

   　　　　P2OUT = shift;

     　}
　　　 else if (shift == 0x01)
　　　 {
　　　　　P2OUT = (P2OUT << 1);

      }
　　　 else 
　　　 {

    　　　P2OUT = (P2OUT >> 1);

       }

    }

}

 

 // Port1 Interrupt Service Routine

interrupt(PORT1_VECTOR) port1_isr(void) 
{

   if (P1IFG & 0x01) 
   {

     shift　　^=  0x81;

     P1IFG   &= ~0x01;　　// Clear Port 1.0 interrupt flag

   }

}