MSP430 矩阵键盘 if函数问题
我写的矩阵键盘的程序有个问题int KeyProcess()
{
int nRes = 0;;
//判断S1~S4
P1OUT = 0xe0;
if (m10IN == 0) 我按下了这个对应按键 ，我一步一步仿真到这边了，这条语句也执行了为真
nRes = 1; 然后就执行了这条语句，这条语句执行完之后我发现监视里面nRes是个无效的值 压根没有赋值，最后nRes 的值是到最后没有按键按下的时候通过else赋值为0。请叫各位大神这是个什么情况 （我先没有用中断做）
#include "io430.h"
#define led20 P2OUT_bit.P0
#define led21 P2OUT_bit.P1
#define led22 P2OUT_bit.P2
#define m10IN P1IN_bit.P0
#define m11IN P1IN_bit.P1
#define m12IN P1IN_bit.P2
#define m13IN P1IN_bit.P3
#define m14OUT P1OUT_bit.P4
#define m15OUT P1OUT_bit.P5
#define m16OUT P1OUT_bit.P6
#define m17OUT P1OUT_bit.P7
void Delay();
void int_port();
int KeyScan();
int KeyProcess();
void Display(int i);
/******************************************
延时函数
*******************************************/
void Delay(void)
{
unsigned int i;
for(i=0;i<100;i++);
}
/******************************************
显示函数
*******************************************/
void Display(int i)
{
int j;
for(j=i;j>0;j--)
{
led20 = 0;
led21 = 0;
led22 = 0;
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
led20 = 1;
led21 = 1;
led22 = 1;
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
Delay();
}
return;
}
/******************************************
端口初始化
*******************************************/
void int_port()
{
P1SEL = 0;//将P1设置成IO口功能
P1DIR = 0x00;
P1DIR = 0xf0;//将P1.0 1.1 1.2 1.3 设置成输入IO,将1.4 1.5 1.6 1.7设置成输出方向
P1OUT = 0x00;
P2SEL = 0;
P2DIR = 0x07;
P2OUT = 0x07;
return ;
}
/******************************************
键盘扫描程序
*******************************************/
int KeyScan()
{
int nRes = 0;
P1OUT = 0x00;
for(;;)
{
//读取各个管脚的状态
if(m10IN == 0 || m11IN == 0 || m12IN == 0 || m13IN == 0)//检测是否有按键按下
{
break;
}
}
Delay();
if(m10IN == 0 || m11IN == 0 || m12IN == 0 || m13IN == 0)//检测是否有按键按下
{
nRes = KeyProcess();
}
else return -1;
return nRes;
}
/******************************************
键盘分析程序
*******************************************/
int KeyProcess()
{
int nRes = 0;;
//判断S1~S4
P1OUT = 0xe0;
if (m10IN == 0)
nRes = 1;
if (m11IN == 0)
nRes = 2;
if (m12IN == 0)
nRes = 3;
if (m13IN == 0)
nRes = 4;
//判断S5~S8
P1OUT = 0xd0;
if (m10IN == 0)
nRes = 5;
if (m11IN == 0)
nRes = 6;
if (m12IN == 0)
nRes = 7;
if (m13IN == 0)
nRes = 8;
//判断S9~S12
P1OUT = 0xb0;
if (m10IN == 0)
nRes = 9;
if (m11IN == 0)
nRes = 10;
if (m12IN == 0)
nRes = 11;
if (m13IN == 0)
nRes = 12;
//判断S13~S16
P1OUT = 0x70;
if (m10IN == 0)
nRes = 13;
if (m11IN == 0)
nRes = 14;
if (m12IN == 0)
nRes = 15;
if (m13IN == 0)
nRes = 16;
else nRes = 0;
P1OUT = 0x00;
//按键释放
for(;;)
{
if (m10IN == 1 && m11IN == 1 && m12IN == 1 && m13IN == 1)
{
break;
}
}
Display(nRes);
return nRes;
}
int main( void )
{
WDTCTL = WDTPW + WDTHOLD;
BCSCTL1 = 0x47;//最高时钟
BCSCTL2 = 0x80;
int_port();
while(1)
{
KeyScan();
}
return 0;
}
受字数限制 我删除了函数的声明 和一些注释
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