1.
INTRODUCTION
The PowerUSB-Watchdog is a device that supplies power to the computer and also monitors for computer
hang-
ups. It reboots the hung-up computer to a clean power-up state. It significantly improves reliability of
remote computers by actively monitoring for software heartbeats. It can also power down the computer for
up
to a 12-hour period, conserving power on computers that are not used all the time. This feature will
also
prevent hang-ups during shutdown and start the computer with a clean state every day. Similar to the Basic
unit,
the Watchdog can monitor the network connection and reboot a hung modem. It can also monitor and
record power
consumed by thecomputer and other peripherals.
Watchdog features can be used with the standard application software provided with PowerUSB and can
also be integrated into other software by using API libraries available for download
from
http://www.pwrusb.com/downloads.html.
1.1
Active Monitoring
The PowerUSB-Watchdog expects a regular heartbeat from the software of the attached computer. When the
computer hangs, the software stops sending the heartbeat to the Watchdog. When the heartbeat is missed for
a pre-determined period of time, the Watchdog powers down the computer and reboots it. The computer then
starts with a clean boot-up state.
After power-down and reboot, the Watchdog stops monitoring the computer (until re-enabled by the
software).
Once up and running, the Watchdog’s software can re-enable monitoring to start a new cycle. This
forced-enable feature will ensure that the software sending the heartbeat is alive during monitoring. Figure 1
shows the flow of logic for this monitoring within the PowerUSB-Watchdog.
1.2
Shutdown-Off-On feature
This feature is available starting with firmware revision 2.2 (displayed in the title of the application next
to the
model name).
PowerUSB software running on the computer can send a signal to the Watchdog strip to “Power me down after
a
period of ‘x’ minutes and power me back on after a period of ‘y’ minutes.” The application will call for a
Windows
shutdown before the computer’s power is switched off. Watchdog will power down the outlet after
the computer is shutdown. The advantages of this feature are as follows:
-
Prevents hang-ups during computer shutdowns
-
Starts the computer in a clean state every day
-
If computer is used only for partial days, it can be automatically powered down for non-usage times.
This will:
o
Conservepower
o
Improve the computer’s useful life
1.3
Log file
Similar to the Basic PowerUSB, the Watchdog application stores all Watchdog-related events and periodic
‘
power consumed’ readings in a log file in the application data directory. This directory can be accessed by
typing “%AppData%/PowerUSB” in the programs and files search bar. The name of the log file is called
PwrUSBLog.log. This is a text file that can be opened with notepad or any other text editor.
