MSP430F5529 GPIO按键是如何去控制LED灯的

按下P2.1开发板上的红绿灯就会同时亮#include "msp430f5525.h"void main(void){    WDTCTL = WDTPW | WDTHOLD;   // stop watchdog timer    P1DIR |= BIT0; //P1.0    P4DIR |= BIT7; //输出P4.7    P2DIR &= ~BIT1; //输入P2.1    P2REN |= BIT1;  //2.1    P2OUT |= BIT1;  //2.1