USB WATCHDOG PRO2
Auto Reboot Device
User manual
www.open-dev.ru!
main@open-dev.ru!
Open Development llc.!
OPEN DEVELOPMENT
USB WATCHDOG PRO2
Product description
USB WatchDog Pro2 is the ideal solution for automatic reboot PC or other devices in case of computer is
frozen. The main idea is to make sure the PC is always available and running, especially for systems that are
not continuously monitored.
Key features
• Two modes for restart PC: push to «reset» pin and «power on/off» pin.
• Windows/Linux/macOS compatible.
• Connection via USB interface.
• Simple protocol allows implement own version of control software.
• Configurable time of waiting the PC signal from 1 to 15 minutes.
• Small size 57х14х10mm(USB TypeA) / 48х14х10mm(USB PBD10).
• Operates in temperature range -40/+85C.
• Doesn’t need additional power supply.
• 2 led indicator.
• Ability to fine-tune the channels and algorithm of operation.
• Ability to limit attempts to restart the PC.
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The device has two modifications: USB TypeA, USB PBD10. !
Both devices have a USB interface, but different way to connection: PBD10 for connecting USB pins on a
motherboard PBD10 socket or a USB TypeA to connect to a standard USB input.
Connection examples:
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USB PBD10
USB TypeA
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USB PBD10
USB TypeA
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Operation
The USB WatchDog device expects a periodic signal from the PC via USB.#If no signal is received for a preset
time t1, the USB WatchDog sends a signal of duration t2 to the Reset contacts.#Further, if the signal does not
appear after the time t1 has elapsed, a signal will be applied to the Power contacts of duration t3, waiting for
duration of t4 and starting with a signal of duration t5.
The source of the signal for the watchdog timer is created by the program (or bat/bash script) running on the
PC. If the PC is freezing, the program usually stops executing, hence the periodic signal disappears, which
leads to the execution of the algorithm set in the watchdog timer.
By default, channel 1 is configured to execute the Reset function, and channel 2 is to perform the Power
function. But for fine tuning, the device allows you to change the function of the channels. Each channel can
operate in one of 4 modes: the Reset function, the Power function, the controlled output or the channel is
disabled.
You can set the same functions on both channels: for example, both reset or power.
If none of the channels is set to reset or power - the internal timer does not start, the device waits for
commands from the PC. This allows you to build your own logic for controlling the watchdog timer (see the
section "Advanced Device Management").
USB connection
• Connect a device with a TypeA connector.!
Connect the device to a suitable connector on the motherboard or PC system unit.!
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• Connection a device with PBD10-R plug
• During installation the device to the mainboard, make sure that you exactly connect to the internal USB
header. Some interfaces (for instance ieee 1394) have the same 10-pins connector on the motherboard.
Connection not to USB interface can cause the damage of device. !
On the version with PBD10 connector there is an arrow on the watchdog board. When connected to the PC
motherboard, it should be aligned with the connector side which has no 1 metal pin.
For the first time, do not connect the device's alarm contacts to the "Reset" and "Power" contacts, because
the software must be pre-installed.!
Note: Be extremely careful when installing the device. Since the device is open-frame, that is, the risk of a
short circuit by touching metal objects or surfaces. This type of damage belongs to non-warranty cases.
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OK
Rotate 180 degrees
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"
Configure
Before using the device, you may need to install device drivers [3]. In the operating system, the device will be
defined as a "virtual COM port".!
A. Windows, the device will be defined as a COM port (for example, COM12).
B. GNU/Linux, the device will be defined as a serial port (for example, /dev/ttyACM0).
C. macOS, the device must be defined as a serial port (for example /dev/cu.usbmodem1421)
A few seconds after turning on the device, the red LED will flash on the device, which indicates the correct
operation of the device and its serviceability. !
To work with the device, a cross-platform program with open source code is proposed [1] [2] [4].
Main window
"
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• When you first start the program, you must click the Scan button and select the COM port of the device in
the drop-down list. If there are no ports in the list or there is only COM1, run the program from administrator.
• When the device is correctly selected, a green "light" starts flashing in the program. At the same time, a
green LED will flash on the device.
• After that, restart the program so that the settings are guaranteed to be saved in the registry.
• If it turned out that after restart the settings were not saved, then the program did not have the rights to
save settings in the registry and it should be run from administrator.
After installing the drivers (if necessary) and setting the software, you can turn off the PC and connect the
Reset and Power signal contacts. Observe the polarity when connecting! Otherwise, during the
functional test, you will not have a PC response to the command (Reset or Power). Please note that
polarity may not be indicated on the motherboard, or it may be incorrect, therefore, it is easiest to establish the
correctness of the connection by the experimental method (see the section "Testing the operability").
Signal contacts of the device:
CH1 and CHA1 – Channel1 parallel contacts. By default, Basic1 should be connected to the «Reset»
contacts, Additional1 to the «Reset» button.
CH2 and CHA2 - Channel2 parallel contacts. By default, Basic2 is connected to the «Power», Additional2 -
to the «Power» button.
IN – A channel for a limit switch or an external temperature sensor DS18B20 connection. This input is directly
connected to the processor. Feeding signals with voltage higher than 3.6V and below -0.6V to this
input will result in damage to the device.
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Testing the operability
To make sure that the device is properly connected to the motherboard, you can force the PC to reboot with
the commands ~ T1 and ~ T2 to test the RESET and POWER signals respectively.
This operation can also be performed using a graphical program, by calling the menu item: "Restart test" and
"Hard reset test" in the pop-up menu in the system tray.
If the command fails, make sure the connection is correct and change the polarity of the connection.
Note: To ensure operation, each program periodically sends a signal to the watchdog timer about its operability.
If the PC "freezes", the program will not be able to send a signal and the watchdog timer will begin its
countdown before the reboot. Therefore, the program should autostart with OS.
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ОТКРЫТЫЕ РАЗРАБОТКИ
Checking the network node using the program. “Network Monitoring” Mode.
In the network monitoring mode, the program updates the device timer only when receiving a positive signal
from ping. This mode is used to reboot when the network connection is lost.
To enable this mode, check the "Network monitoring" checkbox and specify the address of the remote host (ip
or url).
Checking the operability of the process using the program.
In the process monitoring mode, the program updates the device timer only if a process is in the running list
at a given moment.
To enable this mode, check the "Process Monitoring" checkbox and specify the name of the process (as in the
list of processes in the task manager).
Work with input signals. Port IN.
The IN port allows you to connect sources of external signals to the watchdog timer: the digital temperature
sensor, for temperature monitoring or the limit switch for monitoring the opening of the housing, etc.
This channel has a pull-up to a voltage of 3.3V through a 4.7kΩ resistor. It should be remembered that the
input is connected directly to the processor. Feeding signals with voltage higher than 3.6V and below
-0.6V to this input will result in damage to the processor.
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1. Working with a temperature sensor.
An external DS18B20 temperature sensor can be connected to the I / In USB WatchDog Pro2 input.
For this, the combined inputs GND and VDD of the sensor DS18B20 are connected to the "-" input,
and to the "+" DQ of the sensor.
Input to the program (parameter IN channel) should be set to "Temperature".
If the temperature sensor is connected, the temperature data can be periodically read by the ~ G
command (see Table 1 of the "Advanced Device Control" section). The temperature data should be
read no more than once in 3 seconds.
If the value of Temperature threshold (critical temperature threshold) is set to more than 0, the
automatic temperature control mode!
2. Automatic temperature control mode.
To enable the mode, you must set the input to the operating mode with an external temperature sensor
(Temperature), and also set a non-zero threshold temperature. USB WatchDog analyzes the temperature
value every 3 seconds. When the temperature is exceeded, the same actions are performed as for the
timer overflow, which are determined by the channel configuration. For example, it is possible to configure
automatic restart or shutdown of the device in case of overheating.
3. Working with a discrete input.
To enable the mode, you must set the input to the mode of operation with an external signal. It is possible
to connect the normally closed / normally opened limit switch to the input Вх / In USB WatchDog
according to the figure:
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It should be remembered that the input is connected directly to the processor. Feeding
signals with voltage higher than 3.6V and below -0.6V to this input will result in damage to
the processor..
Restriction of the number of attempts to restart the system with a watchdog timer
By default, the watchdog tries to reboot the PC for an unlimited number of times in a row. If you want
to limit the maximum number of successive reboot attempts, you must set the Reset Counter
parameter value to be nonzero (1-15). For example, if you set the value to 10, the watchdog repeats
10 cycles of the PC reset (Reset + Power), turns off the machine and stops while waiting for the
command. Each attempt to execute a Reset or Power is counted as one, i.e. With 10 attempts being
made - it will be 5 attempts of Reset and 5 Power. If one of the channels is disabled, for example, only
Power is activated, then it will be 10 attempts to reboot by clicking on the Power in a row.
Advanced device management
For integration with other systems, the device has a simple text protocol: each command starts with a "~"
signal, followed by a command and an optional parameter
Table1. List of supported commands
Command
Value
~U
The periodic signal from the PC.
~Sx
Set channel x (1 or 2) to state 1 (for GPIO mode)
~Rx
Set the channel x (1 or 2) to 0 (for GPIO mode).
~Tx
Test operation: (1 - Reset; 2- Power).
~Px
Set the timer to pause - 1, remove from pause - 0.
~Mx
Commands for controlling remote devices: 1 - Reset, 2 - Power.
~Lx
0 - disable the light cycle indicator, 1 - enable.
~B
Reboot the module.
~D
Switch to the bootloader.
~I
Get the firmware version
~G
Get the input channel info. See Table 2.
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$
Table2. The response of the device to the command.
!
Table3. Parameters.
~Wxxxxxxxxxxx
Write parameters. See Table 3.
~F
Reading parameters. See Table 3.
Command
Value
Command
Response
~U
~A
~Sx
~Sx
~Rx
~Rx
~Tx
~Tx
~Px
~Px
~G
~Gxxxx (See Table2).
~I
Firmware info
~Wxxxxxxxxxxx
Response with the F command ("Reading parameters").
~F
Reading parameters (See Table3).
~Lx
~Lx
Parameter
Units
Description
1
1 min*
Time before reboot (t1).
2
100 ms*
The duration of the «Reset» signal pulse (t2).
3
1 s*
The duration of the «Power» signal pulse (t3).
4
1 s*
The duration of the waiting time (t4).
5
100 ms*
The duration of the "Power" signal pulse (t5).
6
Channel mode 1: 0 - off, 1 - RESET, 2 - POWER, 3 - controlled
(start state - open), 4 - controlled (start state - closed).
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*The values of parameters 1-5 can be in the range 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A (10), B (11), C (12), D (13), E
(14), F (15).
!
Examples of using the device without a control program.
Windows
• Basic script example:
The portname parameter specifies the device port.
The command ping -n 2 127.0.0.1> nul creates a pause equal to n-1 seconds.
!
7
Channel 2 mode: 0 - off, 1 - RESET, 2 - POWER, 3 - controlled
(start state - open), 4 - controlled (start state - closed).
8
Set reload limit. 0 - no limit.
9
Channel 3 (I / In) mode: 0 - off, 1 - quantized input, 3 temperature sensor input ds18b20.
10
Temperature threshold for an automatic reboot. Actual for
channel 3 (I / In) set to the temperature sensor interrogation
mode. It is set by the value of the threshold temperature in
hexadecimal format, for example: 32 degrees - 20, 80 degrees 50, 00 - disabled.
11
Parameter
Units
Description
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@echo off"
SET portname=COM12"
:loop"
set /p x="~U" <nul >\\.\%portname%"
ping -n 2 127.0.0.1 > nul"
goto loop#
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• Node availability check script:
This script checks the availability of the host specified by the hostname parameter.!
The portname parameter specifies the device port.
The command ping -n 2 127.0.0.1> nul creates a pause equal to n-1 seconds.!
Linux. BASH.
• Basic script example:"
The PORT parameter specifies the device port.
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#!/bin/bash"
PORT=/dev/ttyACM0"
while true"
do"
echo -n "~U" > $PORT"
sleep 1"
done
@echo off"
SET hostname=open-dev.ru"
SET portname=COM12"
:loop"
ping -n 1 -l 4 -w 1000 %hostname% >nul"
if %errorlevel%==0 set /p x="~U" <nul >\\.\%portname%"
ping -n 2 127.0.0.1 > nul"
goto loop
• Node availability check script:
The PORT parameter specifies the device port.
Technical characteristics.
Category
Value
Supply voltage USB, V
5 ± 10%
Maximum current consumption for all active channels, mA
80
Output Type
Transistor optocoupler
Maximum output voltage, V
35
Dimensions USB TypeA / USB PBD10, mm
57х14х10/48х14х10
Operating temperature range, С
-25…+70
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#!/bin/bash"
HOST="open-dev.ru""
PORT=/dev/ttyACM0"
while true"
do"
if ping -c 1 $HOST; then"
echo -n "~U" > $PORT"
fi"
sleep 3"
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Warranty
The warranty period is 12 months from the date of production or 6 months from the sale to the end user.
Malfunctions revealed during the warranty period, caused by the fault of the manufacturer, are repaired at the
manufacturer's expense.
The manufacturer is not liable for damage to property and health caused to the consumer and / or third parties
as a result of actions during installation, commissioning and operation of the product.
Repair and maintenance of products with expired warranty period is carried out at the expense of consumer
funds.
Delivery to the place of warranty repair is carried out at the expense of the consumer
Download.
1. Application source code: https://bitbucket.org/Rdmr/open-dev/src
2. Applicaition download link Win/Lin/OSX
3. Driver for Windows:!
32х https://open-dev.ru/software/VCP_V1.3.1_Setup.exe!
64х https://open-dev.ru/software/VCP_V1.3.1_Setup_x64.exe
4. Support: support.open-dev.ru
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