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GOWORK Management
...GOWATCH Dog
Power
The board is connected in parallel to the reset and power connectors on the motherboard. Two short cables connect the GOWATCH Dog board and the motherboard and the original cables connect from the case switches to the GOWATCH Dog board.
The GOWATCH Dog board is powered externally with the mains to DC adapter supplied. Polarity is not important.
The power supply should be connected to the board before mains power is applied as the outer connecter can short to the board bracket.
Demo programs
The board is shipped with a number of demo programs for integration into the users software.
The driver is loaded with a standard INF file, but at installation, all that is necessary is to make sure the following files are copied to the following directories:
WIN2K and WIN98
PlxApi.dll to system32
Pci9030.sys to system32\drivers
Dslave
Dslave is a program that calls or monitors the driver and indirectly the CPU on the GOWATCH Dog board.
If called without an argument Dslave starts a monitor loop checking for a bit to indicate that a software shutdown is required. If the operating system is not locked up, this will shut down the system and perform a restart.
If the GOWATCH Dog board is set to reset mode a reset will be issued to the motherboard after a delay. If the board is set to power mode the system will be powered off and then powered on. This is sometimes required with raid systems that may need a full power cycle to bring the drives back online.
If the Dslave program is called with an argument (see below), a toggle is sent to the CPU on the board and two calls are processed as one count.
The following program demonstrates a simple application for calling the driver. This of course could be a web server or other application server etc. The following code sleeps for half a second, toggles the board, and then prints the message "PCWD called":
#include
#include
#include
#include
void
main(int argc, char * argv[])
{
for(;;) {
Sleep(500);
system("dslave 1");
printf("PCWD called \n");
}
}
While the board is being toggled it will send status information out of the RS232 connector. This can then be connected to the monitored system via a serial port direct to a PC or to a serial-to-TCP converter to be monitored over the Internet. This can also be used for setting and checking the board.
The program running on the GOWATCH Dog board has been designed to count the toggles and re-boot the system if no toggles are received within one windows period. To stop crashing, it was decided early in the development phase, to wait for the first toggle before checking for missing toggles. This is to stop a situation where a server, for example, has just crashed and been restarted. In this situation, the disks may have the dirty bit set and a system clean is being performed (Scan Disk). This would then take an indefinite time dependant on the size of the storage devices and so would be nearly impossible to set a timer that would start the Watch Dog process.
Under Windows 2000, the demo command line monitor program will shut the system down. Under Windows 98 the shutdown program has to be a win32 window application, so for demo purposes a program called win98shut.exe is supplied. This is called from the Dslave program. It forces an abort of all tasks and forces a system re-boot. This is backed up by the hard-wired reset and power down relays on the GOWATCH Dog board.
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