main.cpp

00001 #include "mbed.h"
00002 
00003 DigitalOut led(LED1);
00004 
00005 class Watchdog {
00006 public:
00007     void kick(float s) {
00008         LPC_WDT->WDCLKSEL = 0x1;                // Set CLK src to PCLK
00009         uint32_t clk = SystemCoreClock / 16;    // WD has a fixed /4 prescaler, PCLK default is /4 
00010         LPC_WDT->WDTC = s * (float)clk;         
00011         LPC_WDT->WDMOD = (LPC_WDT->WDMOD|0x3);                   // Enabled and Reset, without clear WD time-out flag.        
00012         kick();
00013     }
00014     
00015     void kick() {
00016         LPC_WDT->WDFEED = 0xAA;
00017         LPC_WDT->WDFEED = 0x55;
00018     }
00019     
00020     /* You only can do IsWatchdogReset once... because flag must be cleared. */
00021     bool IsWatchdogReset() {
00022         if (LPC_WDT->WDMOD & 0x4) {
00023             LPC_WDT->WDMOD=(LPC_WDT->WDMOD&(~0x4)); /* Clear timeout flag. */
00024             return true;
00025         }
00026         else return false;
00027     }
00028 };
00029 
00030 Watchdog w;
00031 
00032 int main() {
00033     /* First activate WD */
00034     w.kick(2.5);
00035     
00036     printf("Hello World!\n");
00037     
00038     if (w.IsWatchdogReset()) 
00039         printf("MAIN: WD RESET Power up!!\r\n");
00040 
00041     int hang = 0;
00042     while(1) {
00043         printf("loop...\n");
00044         wait(0.1);
00045         
00046         if(hang == 10) {
00047             while(1);
00048         }
00049 
00050         w.kick();
00051         hang++;
00052     }
00053 }