BERKSHIRE PRODUCTS PC Watchdog, Руководство по оборудованию, Страница: 13 / 19

5.
LEDs and Buzzer
5.1 Dual LEDs
There are two LEDs on the back of the board. After the PC powers up the PC Watchdog will wait a
programmed amount of time (set by the switch option) before it enters its watchdog mode. During this
time the top LED will pulse at a 1 second rate (1 second on, 1 second off).
When the PC Watchdog is ready and armed it will start flashing the top LED at a 300 milli-second rate
as an indication that it is running OK. When the watchdog is within 4 seconds of resetting the PC it
will flash this LED at a 1/10 second rate.
If the watchdog board resets the PC, the top LED will return to its one-second toggle rate while it waits
again for the PC to undergo a new reset sequence. When this occurs, the bottom LED will be forced on.
This LED can be cleared by cycling power on the PC, pressing the front panel reset button, or by a user
program. If the watchdog board is receiving re-triggers then it will flash the bottom LED for 100 milli-
seconds during each second.
5.2 SMT USB Active
This surface mount LED is located next to the USB socket on the board. This LED will flash rapidly
when you first plug in the USB to indicate the enumeration process. After the device has been
configured then this LED may flash to indicate USB activity.
5.3 Buzzer
There is a buzzer installed on the board. When the first temperature trip occurs the buzzer will beep.
When the second trip point occurs the buzzer will be on continuously. The buzzer will sound briefly
when the board resets the PC and when the board powers up. If the board has a power up problem it
will emit another long 1 second beep.
There are buzzer options in the supplied DLL and the BPI_WDog_Config program that allow you to
disable the buzzer and change the length of time it sounds at reset.
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