Watchdog Timer Support

[Zibeo]

Is there any documentation for the watchdog timer on Windows XP? I'd like to be able to make use of it in an application and am unsure how to reset it, or "kick the dog" as they say.

[Leonid]

Hi.

Currently, WindowsXP doesn't support watchdog.

However, here is an example how to manage the watchdog through I/O operation in DOS:

void SendData( unsigned char command ,unsigned char data )
{
outp(0x4c,command);
delay(100);
outp(0x48,data);
delay(200);
}

void EnableWatchd(unsigned char time)
{
SendData(1,1);
SendData(2,time);
}

void DisableWatchd()
{
SendData(1,0);
SendData(2,0);
}

Watchdog operation:
To enable or disable the watchdog one should enter BIOS (F2) and go to "Advanced" menu , changing "Watchdog Timer" option to On/Off accordingly.

While this option is disabled user can't change "Watchdog Timer Value ". When enabled one can set 31-255 s operational range .

Entering setup temporary disables watchdog operation regardless to current state.

Once watchdog was enabled the system will be restarted very "Watchdog Timer Value " period , so to prevent it user can restart or disable the watchdog.

[Zibeo]

Do you have any more documentation regarding the watchdog timer? For example the make and model of the chip? I want to give a developer as much info as possible so they can integrate it into an application. I assume it's possible to be able to reset the watchdog in XP if it can be done in DOS.

[Leonid]

Hi.

We have no more information regarding this specific issue.

Best Regards,

[Zibeo]

Is the lack of support in XP due to a lack of driver?

[Leonid]

Yes. There is no native driver for Watchdog Timer in WinXP.