Smart Terminal Parameter Examples

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What/Why/How the Parameter File

A lot of the behavior of the terminal is controlled by the file Different projects of mine require different parameters. The first that might spring to mind are the port and baud rate for the terminal. But the parameter file can change so much more some are simple like adding a colored band to the terminal ( useful if you have more than one terminal running at a time ) to adding whole new modules that modify the graphical user interface ( GUI ) and add automatic processing. While this file has the basic structure of a asci text file, you should keep in mind that it is an executable Python file. This means it is programatic, you can use any Python you want ( pretty much ) but try to limit yourself to setting the value of instance variables in the parameter object.

Different Approaches

  • To start with you can just run with the parameter file as shipped. This gives a reasonable terminal that runs fine, but probably will not run with the baud rate and comm port that you desire so almost for sure you will need to adjust these. There are lines near the top of the parameter file to do this. For more info see the section below.
  • Another method is to use different parameter files for different projects. These might be copied into the smart terminal directory when you want to use them. Works fine but is cumbersome. Start from my file and modify. I do not recommend this approach, but you may want to do it.
  • You can also use a secondary parameter file that overrides the settings in the first file. This is great if you want to run 2 copies of the terminal. Which secondary parameter file is used is controlled from the command line. For more info see the section below. ( coming soon )
  • The subroutine method. This is what I recommend for most uses. It is easy to manage and easy to switch between parameter sets. This is the method in the supplied parameter file and the one that I will use for may discussion of how the parameter file works in genera. The parameter file is heavily commented and these comments should be read if you have questions. You can also search other files for where xxx is the name of the parameter you are investigating.

How to Edit the Parameter File

Yous can use any editor you want ( for text type file ). One warning, however, is not to use an editor that inserts tab characters, tabs are ok if they are converted to spaces but not otherwise. Use your Python editor, that should be fine. For an external editor I use notepad++ on windows but make sure you use the tab to spaces conversion option ( google it ). The parameter file can be set up ( .ex_editor ) so that a button on the GUI will open the parameter file in the editor. After saving the file you can get a very fast restart of the app with the new parameter using the <Restart> button.

Structure of the Default Parameter File

In the __init__ method after a couple of required lines that help hold the application together there is a call to self.default_terminal_mode(). This subroutine sets a ton of parameters and this is enough to make the terminal run nicely. See the comments in the subroutine for more info.

I then have a call to a short ( so far ) subroutine called os_tweaks( ). This subroutine uses a parameter identifying the OS you are running on to tweak some of the settings. These may be useful to you or not. Change them if you want.

In a similar way there is a subroutine called self.computer_name_tweaks( ) This subroutine uses the already/automatically set parameter computername to tweak a few settings depending on the computer's name. This makes it easy for me to change the default parameters setting based on the computer I am using to run the program. Thus I can move the program around without changing the parameter file. These setting, as shipped, are probably not useful to you, but they may be useful as an example.

Finally I make a call to a subroutine like: well_monitor_mode(). This is the file for an arduino project that monitors my water well pressure. This is a pretty complicated set up, because of the database access in the well monitor. For this documentation I will do a subroutine called tutorial_example_mode() which make the most basic changes from the default mode.

Subroutine Method


This mode just changes the default baudrate and the buttons/default data for the button. Read the comments ( here or better in the actual file ) , they are pretty clear:

    def tutorial_example_mode( self, ):
        this mode does not do anything usefull except illustrate a simple "mode subroutine"
        self.mode              = "TutorialExample"  # this name will appear in the title of the window
                                                    # to help keep track of which mode you are using

        self.baudrate          = 19200              # changes the baucrate from the default to 19200

        # the send_ctrls is a list of 3 valued tuples
        # for each item in the list you will have a "send button", a button that will send the contents of
        # the data entry field to the right of it to your comm port.
        # the first item of the tuple is a sting whose test will be on the button
        # the second is a string with the initial or default value for the data entry field 
        # the third is a boolean, True make the data entry field editable, otherwise it is protected from edit
        self.send_ctrls = [
                # text                      cmd               can edit
                ( "Send",                    "",              True ),
                ( "Send",                    "",              True ),
                ( "Different Title",         "default",       True ),
                ( "More Different",          "yes different", True ),
        # you may get extra buttons with default values to fill the space

Another example mode

make it a bit more complicated.



  • logger_id: the id used in the logging file
  • pylogging_fn: file name for the python logging
  • logging_level: python logging level of severity for message to be logged to the logging file
  • win_geometry: the size of the window when first opened
  • ex_editor: name of an executable file used to edit files related to the terminal

Comm Related

  • port_list: a list of ports that the automatic connect routine will use to find a connection
  • port: default port to open
  • baudrate: comm port baudrate
  • serialAppend: characters ( like cr and lf ) placed at the end of transmitted strings
  • auto_open = False # true to open port on start up #  !! *todo
  • prefix_send: a prefix shown in the "receive area" to show that the data has been sent
  • prefix_rec: a prefix shown in the "receive area" to show that the data has been recieved
  • prefix_info: a prefix shown in the "receive area" prefix for informational messages
  • echoSend: locally echo the sent characters
  • get_arduino_version: string sent to get arduino to respond with its version string
  • arduino_version = "GreenHouse" # should be part of the string th
  • arduino_connect_delay = 10 # may not be implemented yet
  • gui_sends = 15 # number of send frames in the gui beware if 0
  • max_send_rows = 3 # the send areas are added in columns this many rows long, then a new
  • default_scroll = 1 # 1 auto scroll the recieve area, else 0

Extended Processing

If you want to add some of your own GUI and processing elements to the terminal the next parameters add a module name and class name that will be loaded into the application

  • ext_processing_module: module name
  • ext_processing_class: class name

Automatically Set

  • our_os: "win32" if your are running windows

For the Second Thread

  • queue_length = 20
  • queue_sleep = .1
  1. ---------- self.start_helper_function = gh_processing.GHProcessing.find_and_monitor_arduino

start_helper_function = "find_and_monitor_arduino" # now using eval, may need to do same with args, start_helper_args = ( ) # () empty ( "x", ) one element start_helper_delay = 0 # in seconds must be > 0 to start

  1. This is how often in ms to poll the comm port, faster makes it more responsive, uses
  2. more resources
  • gt_delta_t = 50 # in ms -- lowest I have tried is 10 ms, could not see cpu load
  • ht_delta_t = 100/1000. # TIME FOR helper thread polling this uses time so in seconds, sorry for confusion

self.send_array_mod = 5 # see task, send array

  1.  ?? not implemented should it be?

block_port_closed = False # block sending if port is closed # *todo -- or some warning


  • id_color: color for an "ID pane" just below the title bar of the window
  • id_height: height of the "ID pane" if 0 there is no pane
  • bk_color = "blue" # color for the background, you can match the id color or use a neutral color like gray
  • icon: name of icon for the application
  • tile
  • size

Sets the communications parameters. Sometimes a little confusing about port names. The arduino IDE sometimes is better at finding the name, check it. Also use the <Ports> button on the GUI. On the apple we have found from <Ports> ('/dev/tty.usbmodem1411', True) and in the parameter file using self.port = "/dev/tty.usbmodem1411" gave a good connection. Sometimes a reboot will result in a change of the port name. Specifies a program for file editing.

Defaults data to be sent. Change number of send areas.

More on Particular Parametes

Parm 1

Parm 2

Using a Second Parameter File

If you running 2 instances of the SmartTerminal you probably do not want to run with the same parameters ( they would use the same comm port ). So if they run with different parameter files they can be quite different. The idea here is they start with the same parameter file, and are then extended with a second file ( say or any other name you wish ). This is done by using a command line. For example: python parameters=paramaters_a

The difference in this file is the parameters are not self.xx but parameters.xx. Else it is pretty much the same. See the example file

delete soon

  • You should also look at the arduino application and the SmartTerminal extension to support it GreenHouse Monitor Program as they are closely related.
  • Well commented read the file!

What thisParameter File Does

     self.send_ctrls        = [ ( "Version", "v", False ),  ( "Help", "h", False ), "simple default text" ]

In this case instead of just changing the default values of the string to be sent, I have also changed the button text and the editablity of the send field. This is done by using a tuple for any given button in the form ( string_button_text, string_send_default, editablity

  • The terminal can probe the communications ports, find a port that opens, send a string to the arduino, and look for a particular response to verify that it is connected to the desired port. This takes the following settings:

  • Another setting is required for the probe of communications ports. Here it is ( set up for automatic switching between operating systems )

  • Data is saved to a csv file, but what is the file name. Here is its setting:
        # for saving csv data 
        self.csv_filename   = "csv_data.csv"
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