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
   }
}