![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
#include "config.h"
#define LED1 (1 << 19)
#define KEY1 (1 << 18)
void DelayNS(uint32 dly)
{
uint32 i;
for(;dly > 0; dly--)
{
for(i = 0; i < 50000; i++);
}
}
void WDTInit(uint32 uiTime)
{
WDTC = uiTime;
WDMOD = 0x03;
WDFEED = 0xaa;
WDFEED = 0x55;
}
void FeedDog(void)
{
IRQDisable();
WDFEED = 0xaa;
WDFEED = 0x55;
IRQEnable();
}
int main(void)
{
uint32 i;
PINSEL0 = 0x00000000;
PINSEL1 = 0x00000000;
IODIR = LED1;
IOCLR = LED1;
DelayNS(100);
IOSET = LED1;
WDTInit(0x200000);
while(1)
{
while((IOPIN & KEY1) == 0);
for(i = 0; i < 0xff; i++);
FeedDog();
}
}
#include "config.h"
#define LED1 (1 << 19)
#define KEY1 (1 << 18)
void DelayNS(uint32 dly)
{
uint32 i;
for(;dly > 0; dly--)
{
for(i = 0; i < 50000; i++);
}
}
void WDTInit(uint32 uiTime)
{
WDTC = uiTime;
WDMOD = 0x03;
WDFEED = 0xaa;
WDFEED = 0x55;
}
void FeedDog(void)
{
IRQDisable();
WDFEED = 0xaa;
WDFEED = 0x55;
IRQEnable();
}
int main(void)
{
uint32 i;
PINSEL0 = 0x00000000;
PINSEL1 = 0x00000000;
IODIR = LED1;
IOCLR = LED1;
DelayNS(100);
IOSET = LED1;
WDTInit(0x200000);
while(1)
{
while((IOPIN & KEY1) == 0);
for(i = 0; i < 0xff; i++);
FeedDog();
}
}
实验现象,正常情况下:上电后,LED会闪一下。因为定时喂狗,就这样一直不闪了。
我们通过按键来模拟意外事件。
当长按住按键时,因为不能定时的喂狗,所以LED就会不停的闪烁。