Super Watchdog V2 for Raspberry Pi

The Super Watchdog V2 provides the safety required by mission-critical projects, implementing two major functions. It power-cycles the Raspberry Pi 

n case of software lock-up, resetting not only the Pi but also any peripheral attached to it, and it prevents SD-Card failure in case of power loss by allowing the Raspberry Pi to shut down itself safely.

This is the new Sequent Microsystems Super Watchdog V2 - which now provides a full 3A of power and includes three power connector options, including USB-C for Raspberry Pi 4 power supplies!

The barrel power connector, which was rated 2A on the V1 board, has been replaced with a 5A version. The step-up power supply which feeds the Raspberry Pi from a battery when the power runs out has been redesigned to now supply a full 3A. Sequent has also added a USB-C type connector, so you can use the power supply which comes with Raspberry Pi 4. To keep compatibility with previous generations there's also a micro-USB connector too.

If you use your Raspberry Pi for any mission-critical project, you need the Super-Watchdog with battery backup. The watchdog measures only 87mm * 28mm but packs a lot of functions.

The watchdog has a default timeout of 120 seconds. Once installed, if it does not receive a reset from Raspberry Pi within 2 minutes, it cuts the power and restores it after 10 seconds.

The Raspberry Pi needs to issue a reset command before the timer on the watchdog expires. The command can be sent either on the I2C port or by toggling GPIO11 (Pin 23 on the GPIO connector). The timer period after power up and the active timer period can be set from the command line. The number of resets is stored in flash and can be accessed or cleared from the command line.

Technical support provided directly by Sequent.

Note: Raspberry Pi and 18650 battery not included

Self Test

The Raspberry Pi Watchdog has onboard hardware to self check all the major functions. Self-check is performed at each power-up. The on-board LED is flashed rapidly (5 times per second) if a hardware error is detected, or slowly (1 time per second) to indicate normal functionality. The LED is turned on if the watchdog resets the Raspberry Pi, and off is the Raspberry Pi is powered down for a specific time interval.

Compatability

The Raspberry Pi Watchdog is compatible with all Raspberry versions with 40 pins, including the Pi Zero. The card shares the I2C bus using only two of the Raspberry Pi’s GPIO pins. This feature leaves the remaining 24 GPIOs available for the user.

Battery Operation

The 18650 Li-Ion battery (not provided) can keep the Raspberry Pi running for hours, assuring continuous operation during power outages.

When running on battery power, the watchdog processor monitors the battery voltage. To prevent permanent damage to the battery due to over-discharging, the processor will cut off the power to Raspberry Pi when the battery drops below 2.8V.

A software command is available to the user to also monitor the battery voltage. It is strongly recommended that Raspberry Pi performs a self-shutdown then the battery voltage drops to 3.0V.

Power Requirements

The Raspberry Pi Watchdog needs 5V to operate. For your convenience, the board is equipped with three power connectors: USB-C, micro-USB and a 2.1mm barrel connector found on many standard 5V power supplies. In order to operate, the watchdog must provide the power to Raspberry Pi.

Software Interfaces

If you are a software wiz, write your own Home Automation program in C, C++, PERL or the language of your choice using the Command Line system or Python Drivers.

Quick Start-up Guide

• Plug your SUPER-WATCHDOG card on top of your Raspberry Pi and power up the system from the watchdog.
• Enable I2C communication on Raspberry Pi using raspi-config.
• Install the wdt software from github.com:
  
  • git clone https://github.com/SequentMicrosystems/wdt-rpi.git
  • cd /home/pi/wdt-rpi
  • /wdt-rpi$ sudo make install
  • /wdt-rpi$ wdt
• The program will respond with a list of available commands.

Package Content

• 1x Super Watchdog V2
• 1x Fixings pack (2x screws, 2x nuts, 2x standoffs)

Raspberry Pi and Battery not included