How To Run

After all the required packages have been installed, type

python mainwindow.py

or

python3 mainwindow.py

in your favorite terminal.

Quick Introduction

The default starting address is opc.tcp://0.0.0.0:4840. This can be easily changed by typing a new address in the Server Address line. The program will not let you add any devices until the server has been started.

Click "Start Server" to start the OPC UA server. The "Server Status" will change from "Not Running" to "Running" if the server has been stared successfully.

You can add devices by using the "File" menu item at the top and then selecting "Add Directory" or "Add File." See the "Device XML Structure" if you'd like to try to make your own from scratch. There is also "test_file_2.xml" in the devices_and_timers folder as an example.

If you have successfully imported files, you should see the devices listed in the tree on the left hand side.

Newest version now has the option of displaying plots for historized variables:

This screenshot shows a RampRandom variable plotted:

If you have added the server to your Ignition Gateway, you can see it listed in the OPC browser.

You can drag and drop the items into your tags folder

Timers

Each variable in the program has a timer associated with it. A timer fires either after a set amount of time every time, called periodic, or a random amount of time between give low and high values called random.

When a timer fires, it evaluates all functions that are associated with it.

For example, a random timer with min 2.5 and max 80, can be called at any values between 250 ms and 80,000 ms. A periodic timer with timeout set to 2 will fire every 2 seconds.

Functions

Every variable has function defined for it. The following list are all the available functions for variables. There are plans to add more functions.

Every function has a "repeat" and a "historize" in its XML definition.

• repeat = True means repeat indefinitely, False means stop after period
• historize = True means to keep a history of values. Current max time of keeping history is 2 hours. This can be changed by editing the following line in value_function_classes.py:

    self.number_of_history_hours = 2

ValueList

This function takes a list of values and then iterates through the list in order. The function can iterate through a set number of times or indefinitely.

Example

[1, 3, 2, 4, 6], Period = 3, Repeat = False: This would cause the variable to take on the values 1, 3, 2, 4, 6, 1, 3, 2, 4, 6, 1, 3, 2, 4, 6 and then stop on 6. Having Repeat=True discards any value period

XML Function Element

• values = list of values the variable will take; note that the order given is the order the variable will use
• period = number of times to repeat; NOTE: This is different than most other functions in that this is not True/False, but an integer.

WeightedList

This function takes a random sample from a list created from a value and weight lists. If the values is [v_1, v_2, ..., v_n] and the weight list is [w_1, w_2, ..., w_n], then the random sample is take from w_1 copies of v_1, w_2 copies of v_2, ..., and w_n copies of v_n. Note that the weight list must be integers.

Example

values = [1, 4, 5] and weights = [9, 2, 1]. The random sample is taken from [1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 4, 5]. Thus the probability of 1 is 3/4, probability of 4 is 1/6, and 5 is 1/12.

XML Function Element

The XML function element "weightedlist" must contain:

• type = 'weightedlist'
• values = list of values in brackets [] (might have a different name in your country)
• weights = list of values in brackets [] (might have a different name in your country)
• period = number of times the random sample should be taken; if repeat set to True, random sample will be taken indefinitely

RampStep

The variable increments the same given value every time its associated timer fires. Once the variable reaches its maximum, it will reset to the given minimum.

XML Function Element

• type = 'rampstemp'
• min = minimum value the variable should take
• max = maximum value the variable should reach
• step = amount to increment each time its associated timer fires

RampPeriodic

The amount the variable increments depends on the elapsed time between when its associated timer fires. For periodic timers, the amount incremented will be the same. However for random timers, the increment value will differ. This ensures that the variable will reach its maximum every period. In contrast, the RampRandom has no period and thus not guaranteed to reach its maximum in any given time frame.

Example

Take minimum = 200, maximum = 10,000, period = 440, and has a periodic timer set to fire every 10 secs. The variable will then increment by around 223 each time the timer fires.

XML Function Element

• type = 'rampperiodic'
• min = minimum value the variable should take
• max = maximum value the variable should reach
• period = number of seconds for the ramp to repeat

RampRandom

Randomly increments by a value in an interval. If the value is above the given maximum, it will start over at the minimum.

Square

The variable will take on one of two values given by min and max. Period is the minimum number of seconds the variable should stay at a value before switching.

XML Function Element

• type = 'square'
• min = The value the variable will take on first.
• max = The value the variable will take on second. Note that max can be less than min.
• period = Minimum number of seconds the variable should stay at each value.

RandomSquare

Randomly takes on one of two given values.

XML Function Element

• type = 'randomsquare'
• min = one possible value the variable will take
• max = the other possible value the varialbe will take
• period = number of seconds the function should spend switching between min and max; if repeat is set to true, this has no purpose

Triangle

Makes a sawtooth function that oscillates between min and max.

XML Function Element

• type = 'triangle'
• min = minimum value the variable should take
• max = maximum value the variable should take
• period = number of seconds in which one tooth is made

Sin

Makes use of the sin function.

XML Function Element

• type = 'sin'
• min = minimum value the variable should take
• max = maximum value the variable should take
• period = number of seconds in which one period of the sine function is executed

Cos

Makes use of the cos function.

XML Function Element

• type = 'cos'
• min = minimum value the variable should take
• max = maximum value the variable should take
• period = number of seconds in which one period of the cosine function is executed

Device XML Structure

The base tag is "simulator." The sub-element "timers" contains all the definitions for timers that are to be used for the variables.

The next sub-elements are "device." There can be 1 or many "device" sub-elements of "simulator." Each "device" element must contain

• name
• datatype
• timer (timer name must be listed in the timers section)
• function

The function element contains many sub-elements that depend on the function used. The required elements are listed above in the "XML Function Element" section of each function.

Future Plans

• Devise a way to change number of hours for history to be editable by user.
• Fill in pane above the graph to include information about the selected variable, such as function, next evaluation, data type, and other node info.
• Allow user to set plot options such as color.
• Add styling to all windows.

Disclaimer

This still needs a lot of work. The GUI is operational and allows for adding/deleting devices. Being able to edit devices and such still needs some work.