Appendix A Watchdog Timer; A.1 About Watchdog Timer; A.2 Watchdog Timer Programming - AXIOMTEK MANO315 Series User Manual

MANO315 Mini ITX Motherboard

A.1 About Watchdog Timer

Software stability is major issue in most application. Some embedded systems are not
watched by human for 24 hours. It is usually too slow to wait for someone to reboot when
computer hangs. The systems need to be able to reset automatically when things go wrong.
The watchdog timer gives us solution.
The watchdog timer is a counter that triggers a system reset when it counts down to zero from
a preset value. The software starts counter with an initial value and must reset it periodically. If
the counter ever reaches zero which means the software has crashed, the system will reboot.

A.2 Watchdog Timer Programming

//**************************************************************
//**
//** Copyright(C) 2018, Axiomtek co., Ltd
//**
//** All Rights Reserved.
//**
//**************************************************************
#include <pc.h>
#include <stdio.h>
#define SIO_Index_Port
#define SIO_Data_Port
#define SIO_Enter_Configuration_Mode 0x01
#define SIO_Entry_key
#define SIO_LDN_SEL_REGISTER
#define SIO_LogicalDevice_GPIO
#define SIO_Offset_Countdown_Type
#define SIO_Offset_Countdown_Timer
#define SIO_Countdown_Type_Second
#define SIO_Countdown_Type_Minute
#define SIO_Exit_Configuration_Mode 0x02
void main() {
int CountdownType=0;
int WDTtimer=0;
//
46
0x2E
0x2F
0x55
0x07
0x72
0x73
0x40
printf("Input Watch Dog Timer type, 1:Second ; 2:Minute :");
scanf("%d",&CountdownType);
printf("\nInput Timer to countdown:");
scanf("%d",&WDTtimer);
printf("Start to countdown...");
// Enter Configuration Mode
//
Appendix A
Watchdog Timer
**
0x07
0xC0
**
**
**
**
Watchdog Timer