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wonham:sctool [Tuesday, 13 February 2007 : 14:13:00] (current)
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 +====== sctool - Supervisory Control Tool ======
  
 +We are developing a more user-friendly Python variant of the Wonham ''​tct''​ tool that can help you develop supervisory controllers.
 +This tool is called //sctool// and it has been installed at our Linux serack systems.
 +
 +Like many of the ''​svctools'',​ ''​sctool''​ has been written in [[http://​www.python.org/​|Python]]. This means that the tool should also run at the Windows platform.
 +Feel free to try it. If you need a Python environment for Windows, you could try [[http://​www.activestate.com/​Products/​ActivePython/​|ActivePython]].
 +
 +===== Installing sctool under Windows =====
 +After unpacking the tar.gz file in a temporary directory, open a Command Prompt window and go to that directory (Where file setup.py is located.) Do the following:
 +  * Make sure you have at least Python 2.3 installed
 +  * Enter the command ''​python setup.py install''​. This should build and install svctools
 +  * In the ''​scripts''​ directory of your Python distribution,​ append the .py extension to the following files: ads2stm, gen-chi, gen-dot, sctool, stm2ads, stm2fsm. This restores the file association with Python. (Linux does not need them, so they are not there)
 +  * Extend your PATH environment variable with the path to the files in the scripts directory so you can call a utility from anywhere...
 +  * Remove the files in the temporary directory where you downloaded sctools.
 +
 +So, to start up sctool for instance, you would enter ''​sctool.py''​ in a Command Prompt window (Select //​Start->​Run//,​ entering ''​cmd''​ as program you want to run gives you a Command Prompt window in which you can start ''​sctool.py''​).
 +After that, you are in the SCT command environment.
 +
 +===== Starting sctool =====
 +Starting the ''​sctool''​ is done by simply entering its name at the command line:
 +<​code>​
 +$ sctool
 +SCT: Supervisory Control Tool, written by H.A. de Vos
 +Copyright (c) 2006, Systems Engineering group,
 +Department of Mechanical Engineering,​
 +Eindhoven University of Technology,
 +The Netherlands
 +
 +Type '​help'​ for a list of available commands
 +SCT$ 
 +</​code>​
 +**Note** While Herman de Vos implemented most code of sctool, he does not maintain the tool. For bug reports, questions, remarks, enhancement requests, and other questions regarding //sctool//, **always contact [[a.t.hofkamp@tue.nl]]**.
 +
 +sctool gives you an interactive environment where you can derive a supervisory controller.
 +In the environment,​ variables exist that contain a Wonham state machine, and you can compute new state machines by entering commands.
 +
 +sctool has no editor for entering a state machine, so you have to prepare them beforehand. Two of the more popular ways of doing this are
 +  * create them with a text editor, or
 +  * create them interactively with another tool, for example ''​tct'',​ then convert them to the correct format.
 +Details about this process can be found at [[creating and editing state machines]].
 +
 +===== Loading and saving state machines =====
 +Once you have the necessary files with state machines prepared, you can load them in ''​sctool'':​
 +<​code>​
 +SCT$ ma = loadsct "​ma.sct"​
 +SCT$ mb = loadstm "​mb.stm"​
 +</​code>​
 +These two commands load files ''​ma.sct''​ (in sctool'​s own file format) and ''​mb.stm''​ (in statemachines file format) into the tool, and assigns them to variables ''​ma''​ respecitvely ''​mb''​.
 +
 +The available variables can be listed by entering
 +<​code>​
 +SCT$ show
 +</​code>​
 +
 +Displaying the contents of a single variable for example ''​ma''​ is done by entering
 +<​code>​
 +SCT$ show ma
 +</​code>​
 +
 +Even for small state machines, interpreting the output is already difficult.
 +To solve this problem, ''​sctool''​ also provides commands for saving state machines. Once saved, you can use other tools to perform further processing steps (eg generate nice pictures of the state machine, or generate chi code).
 +
 +Saving is done by the //save// commands, like
 +<​code>​
 +SCT$ savestm ma "​ma.stm"​
 +SCT$ savesct mb "​mb.sct"​
 +</​code>​
 +which gives you two new files ''​ma.stm'',​ and ''​mb.sct''​ containing the same state machines just loaded, except in the other file format.
 +
 +===== Computing new state machines =====
 +The real power in sctool is that it can compute new state machines from old ones. The table below shows the available commands:
 +
 +^ Example ​          ^ Description ​ ^
 +| ''​p = meet q r'' ​ | Compute the //meet// of machines ''​q''​ and ''​r'',​ and put the result in ''​p''​ |
 +| ''​p = sync q r'' ​ | Compute the //sync// of machines ''​q''​ and ''​r'',​ and put the result in ''​p''​ |
 +| ''​p = trim q'' ​   | Compute the //trim// of machine ''​q''​ and put the result in ''​p''​ |
 +| ''​p = selfloop q [ a b ] [ c ]''​ | Add selfloop of controllable events ''​a''​ and ''​b'',​ and uncontrollable event ''​c''​ to machine ''​q''​ and put the result in ''​p''​ |
 +| ''​p = supcreate [ q r ] [ v w ]''​ | Compute the supervisor for machines ''​q''​ and ''​r''​ with specifications ''​v''​ and ''​w'',​ and put it in ''​p''​ |
 +
 +===== Other commands =====
 +Last but not least, sctool has a few other useful commands. They are listed in the table below:
 +
 +^ Example ​  ^ Description ​  ^
 +| ''​! ls'' ​ | Run a shell command from sctool, in this case "''​ls''"​ |
 +| ''​shell ls''​ | Same as "''​! ls''"​ |
 +| ''​quit'' ​    | Stop sctool ​     |
 +| ''​exit'' ​    | Same as "''​quit''"​ |
wonham/sctool.txt · Last modified: Tuesday, 13 February 2007 : 14:13:00 (external edit)