Internal Serial PC Watchdog Timer Image External Serial OS Watchdog Timer Text Image

Internal Serial PC Watchdog Timer Description

This is a small circuit board that mounts inside the PC and monitors a PC for hardware/software lock-ups. It provides a solution to reboot PC file servers, telecom, security, kiosk, video surveillance, digital signage and industrial systems that occasionally lock up but must be available on a continuous basis. Increase your system availabilty and protect against unexpected downtime or blue screens (BSOD).

The Serial PC Watchdog timer ships with utility programs for control & "tickling" of the board. Sample source code and libraries are also provided in Visual "C" and Visual Basic to allow users to write their own applications to configure or "tickle" the board. Use the CD image download below to see the samples provided along with all the programmer's documentation. The Serial PC Watchdog works with Win 2K XP Vista Win7 Win 8 Server2003 Server2008  (32 & 64 Bit Versions on all). It also has LINUX support.

This device has been tested with USB to Serial devices based on the FTDI and the Prolific chip. It should work fine with other versions also. The board does ship with a 6 foot DB-9M to DB-9F cable.


  • Acts as a pass-through serial port with standard PC DB-9 connectors. Allows you to keep a MODEM or other serial device connected.
  • Monitors the PC serial port for control line activity (TxD, DTR, & RTS) from the PC.
  • Monitors the Ring Indicator (RI) line from a MODEM on the serial port for excessive rings without an answer.
  • Can be used right from the box without any support programs if you already have constant serial port activity.
  • Time-out delays available from 5 seconds to 2 hours
  • Also has a Command Mode that allows a user program to exert additional control over the PC Watchdog.
  • Two externally visible LEDs show status of PC Watchdog.
  • Has an on-board temperature sensor that can be read by user program.
  • PC Watchdog can also reset the PC on an over-temp condition such as a fan failure.
  • On-board buzzer sounds at reset and over-temp condition.
  • PC Watchdog has second relay that a user can control via software
  • Programmable power-on delay to allow the PC to complete its initialization sequence.
  • Can occupy an empty slot in PC cabinet.
  • Gets its +5V power from standard disk drive connector.
  • Comes with Reset Cable and 6 foot DB-9 M-F serial cable.
  • Support for PCs without a motherboard reset header available with: ATX-Reset-Adapter

The Internal and External Serial PC Watchdogs now have full Windows DLL support with the new Universal DLL released in April of 2010. They are also fully supported with the included Config and Tickle programs for all versions of Windows that support Net Framework 2.0 and higher.

Pricing & Purchase Link

This item can be purchased at the Berkshire Products online store.
      Buy Internal Serial PC Watchdog
(Clicking this link will take you to a new site for the store.)

Part# Description Price
1120 Internal Serial PC Watchdog $132.95
CBL-USB-SER-3 USB to Serial DB-9 (RS-232) Adapter - 3 foot $19.95

Note: Short lead times may be required. Please contact Berkshire for further info.


Internal Serial PC Watchdog PDF Manual
- This link is for the latest version of the Internal Serial Hardware Manual.

Universal DLL PDF Programmer's Manual
- This link is for the latest version of the Universal DLL Programmer's Manual which describes all the functions provided in the DLL for users who write their own application programs.

Distribution CD Image File (ZIP File)
- This link is for the current version of the distribution CD that contains all the manuals, programs, drivers, and the sample software. This includes the sample "C" and code for those users who wish to write their own aps or want to incorporate watchdog support into their existing software.

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