[原创] 【TI首届低功耗设计大赛】+@fxyc87+第三课 GPIO中断操作

fxyc87 2014-9-7 15:34 楼主

【TI首届低功耗设计大赛】+@fxyc87+第三课 GPIO中断操作

前三次讲了金刚狼开发板的开发环境，包括CCS,IAR以及一个简单的GPIO触摸实例
其实这个芯片默认输入就可以触摸的，无需其它设置，所有引脚均支持，若关闭只需开启上拉或下拉电阻即可

这次再来个教程
GPIO中断示例
以下所有代码均为本人原创

开发板演示方法：按下S2键，LED2亮

#include "msp430fr5969.h"
//by fxyc87@gmail.com
int i=0;
int main(void)
{
WDTCTL = WDTPW | WDTHOLD; //关闭看门狗
P1OUT=0+BIT1; //初始化指示灯灭+S2上拉，关闭触摸，实体按键
P1REN=BIT1; //上拉启用
P1DIR = BIT0; //P1.0设置为输出
P1IES = BIT1; //1>0 下降沿触发
P1IE =BIT1; //P1.1开启中断
PM5CTL0 &= ~LOCKLPM5; //启用GPIO配置
P1IFG=0;//清除中断标志
_EINT();//开启总中断
while(1){
if(i)
P1OUT |= BIT0;
else
P1OUT&=~BIT0;
}
}
#pragma vector=PORT1_VECTOR
__interrupt void P1IV_ISR (void){
if(P1IV&(BIT1*2)){
i=1;
//P1OUT^=BIT0;
}
P1IFG=0;
}

解说：

#pragma vector=PORT1_VECTOR
这里是中断入口点，关于中断点，
可以在 "msp430fr5969.h"文件最尾部有声明
然后就是开启PXIE相应引脚及总中断_EINT()
P1IV为中断标志位，见手册354页说明或下方文字

引用: Port 1 interrupt vector value
00h = No interrupt pending
02h = Interrupt Source: Port 1.0 interrupt; Interrupt Flag: P1IFG.0; Interrupt
Priority: Highest
04h = Interrupt Source: Port 1.1 interrupt; Interrupt Flag: P1IFG.1
06h = Interrupt Source: Port 1.2 interrupt; Interrupt Flag: P1IFG.2
08h = Interrupt Source: Port 1.3 interrupt; Interrupt Flag: P1IFG.3
0Ah = Interrupt Source: Port 1.4 interrupt; Interrupt Flag: P1IFG.4
0Ch = Interrupt Source: Port 1.5 interrupt; Interrupt Flag: P1IFG.5
0Eh = Interrupt Source: Port 1.6 interrupt; Interrupt Flag: P1IFG.6
10b = Interrupt Source: Port 1.7 interrupt; Interrupt Flag: P1IFG.7; Interrupt
Priority: Lowest