User's Manual

Understanding Security features 127

Figure 38

Berkshire Product Inc. Internal serial PC Watchdog

The Watchdog card is designed to monitor PCs used in critical applications

such as: File Servers, Voice Mail Systems, Internet Service Provider (ISP)

systems, industrial applications, and so on. The purpose of the Watchdog

card is to ensure the PC is always available; especially for systems that

are not continuously monitored. After power is applied to the Watchdog,

or after a reset of the PC, the Watchdog waits 2.5 minutes (shorter times

allowed in Command Mode) before arming itself. This allows the PC to

complete its reset and initialization sequence.

The standard Watchdog package contains the following items:

• The Berkshire Watchdog manual on diskette as a PDF file

• The Watchdog timer on a standard PC I/O bracket

• A disk drive Y style power cable to power the board

• A DB-9 to DB-9 serial cable

• A 3.5 program diskette

• A reset cable

The Watchdog card is an internal PC card but without an ISA or PCI

connector. The unit consists of a bracket with a small card that receives

power from the PC by means of a Power Cable with standard Disk Drive

Power connector. All the signal connections are made externally. Figure

39 "Configuration of the Watchdog card" (page 128) shows how the

Watchdog is used in DECT Messenger.

There is a mini jack connector available at the bracket of the Watchdog

card, which provides two relay contacts. However, these are not used in

the DECT Messenger configuration. The contacts can only be activated

after an application sends the correct commands to the card using

V.24 (RS232). DECT Messenger cannot send such commands to the

Watchdog.

The Watchdog resets the PC if the eKERNEL is not running.

Nortel Communication Server 1000

DECT Messenger Fundamentals

NN43120-120 02.01

11 May 2009