sm_gene

State machine generator, based on statemachine library

Project maintained by technosvitman Hosted on GitHub Pages — Theme by mattgraham

statemachine

Introduction

In many microcontroler programs, without the help of tiny OS (like FreeRTOS), we need to implement a non-blocking state machine. In many programs we just can see the easy way, which will be quite difficult to maintain afterwards : a switch/case called each time in the main loop. This generator build state machine using the library statemachine

Installation

run __install.bat or python -m pip install -r requirements.txt

What is a state ?

A state is described by 3 actions:

on_enter : what to do on enter
do_job : what to do on event
on_exit : what to do on exit

Switching from a state to another is managed by do_job regarding which event is recieved.

What is an event ?

An event is identified by an integer value and sometimes has attached data. For example, an event can be “button pushed” and the attached data can be “the button identifier”

Generator your state machine

This lib integrate a generator to build code basis to build your own state machine.

The input is a YAML file that describe the machine.

The output files are :

*.c file : the source code
*.h file : the header
*.plantuml : UML diagramme in plantuml format
*.png : UML diagramme

These files are stored into generator/output directory

Describe your state machine

{
    "machine" : "", # your state machine name
    
    "entry" : "", # the entry point state name

    "global" : # global state action 
    {
        "actions" : [], #see states
        "enter" : "", #see states 
        "exit" : "", #see states
    }
    
    # the states list
    states : 
    [
        { 
            "name" : "", # sthe state name
            "comment" : "", # some information on the state

            # describes state change and/or action on a event
            "actions" : 
            [
                # an action
                { 
                    "to" : "", # destination state name
                    "conds": 
                    [   # the list of conditions triggering state change
                        {
                            "event": "", #the event name
                            "cond": "", #optional specific condition 
                            "comment": "", # optional event description. You can set only one time the event comment
                        },
                        #another condition
                        {
                            ...
                        }
                    ],
                    "job" : "" # what to do on this event
                },
                # another action
                {
                    ...
                }
            ],
        },
        # an other state
        {
             ...
        }
    ]
}

Build your machine

Call the generator like this from the generator directory :

    python StateMachineGenerator.py -i {path_to_your YAML file}

It stored automaticaly output files with the base name of yout yaml file

You can set a custom output name with the ‘-o’ option

    python SMGene.py -i {path_to_your YAML file} -o {your_custom_name}

Apply your file template

You can describe templates to build the state machine.

You will find exemples in templates directory :

Availables templates are for source and header files.

Source template

filename to use : template_source.c

In the source you may put :

$statemachine_includes : where the modules includes should be inserted
$statemachine_states_dcl : where private states callbacks declaration should be inserted
$statemachine_globales : where modules globales variables should be inserted
$statemachine_states_clbk : where private states callbacks implementation should be inserted
$statemachine_states : where states declaration should be inserted ( has to be after states callbacks )
$statemachine_func : where public function should be inserted

Header template

filename to use : template_header.c

In the source you may put :

$statemachine_begin : where the header content should begin
$statemachine_types : where the machine types should be inserted
$statemachine_func : where public function should be inserted

Generation

Put templates in a directory and start generation with :

    python SMGene.py -i {path_to_your YAML file} -o {your_custom_name} -t {your_template_directory}

Example

You can find the state machine example here :