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Microcontroller:    Microchip PIC18F4550 Requirements:    Star UML (available here)    Microchip C18 Compiler (available here)    .NET Framework 2.0 (not tested with >=3.0) License:      The source code of this work is licensed under a   Creative Commons License.

»  Introduction This project is a plugin for the popular Open Source UML/MDA Platform StarUML . The plugin extends StarUML with some new UML elements for modelling, compiling and downloading an application (via USB) to the microcontroller PIC 18F4550. This project does not comprise full modelling capabilities for all peripherials of the PIC but shall serve as inspiration and/or basis for your own extensions. The following picture shows a screenshot of StarUML with a small application model that creates a changing PWM signal. (click to enlarge) Dashed lines show the object flow (the usage of objects by the activities as input or output) while solid lines are used for modelling the program flow, e.g. the transition between different activities.

»  Installation After having downloaded the ZIP-File containing all required files (including the source files and some demo projects) here you need to unzip the files into the "modules" folder of your StarUML installation. The resulting structure should look like this: C:\Programme\StarUML\modules\visualPic\.... Now you need to make the plugin accessible to StarUML as a COM object. Therefore you need to execute the batch file "register.bat". Note: The Assembly Registration Tool "regasm.exe" must be in your search path for the batch file to work properly. It comes with the .NET framework and should be lokated in "C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727", for example. Now the VisualPIC AddIn is ready for action.

»  Tutorial The following UML elements are available: Element UML base element Purpose Flow start Activity Start of the program flow Assignment Activity Assigns the value of one incoming object to one or more outcoming objects Addition Activity Adds up all incoming objects and assigns the result to the outgoing object IsZero Activity Checks if the value of an incoming object is zero and triggers different successor activities depending on the result GreaterZero Activity Checks if the value of an incoming object is larger than zero and triggers different successor activities depending on the result Delay Activity Delays the following activity by the specified amount of milliseconds (currently the timing is only correct when the PIC uses a 48MHz oscillator) Variable ObjectFlowState Can be used to store or read a variable value Constant ObjectFlowState Read as a constant value BitOut ObjectFlowState Sets the state of a digital output pin BitIn ObjectFlowState Gets the state of a digital input pin PWMOut ObjectFlowState Creates a PWM signal at pin RC2 Objects like Delay or BitIn/Out offer tagged values for modeling specific properties.

»  Some examples 1. Assignment (constant to variable): Generates the following code: int to_a_variable; ... Flowstart:   //Start of the program flow and_assigned_to:   //Assigning 'Constant is read' to 'to a variable'   to_a_variable = 0; 2. Assignment (BitIn to BitOut): Port pins are configured using tagged values (via context menu) Generates the following code: //BitIn initialization... TRISBbits.TRISB4 = 1; //BitOut initialization... TRISDbits.TRISD0 = 0; PORTDbits.RD0 = 0; ... Flowstart:   //Start of the program flow and_assigned_to:   //Assigning 'PortRB4' to 'PortD0'   PORTDbits.RD0 = PORTBbits.RB4; 3. Branch (IsZero): Branches are configured using the transitions' guard conditions Generates the following code: Flowstart:   //Start of the program flow IsZero:   if (PORTBbits.RB4 == 0)   {     goto Delay1;   }   else   {     goto ElseActivity;   } Delay1:   Delay1KTCYx(0); ElseActivity: ... 3. Branch (IsZero): Branches are configured using the transitions' guard conditions Generates the following code: Flowstart:   //Start of the program flow IsZero:   if (PORTBbits.RB4 == 0)   {     goto Delay1;   }   else   {     goto ElseActivity;   } Delay1:   Delay1KTCYx(0); ElseActivity: ...

»  The following table shows a complete overview of the allowed number of successor/predecessor objects and activities for each available activity type: Activity Objects Activities in out in out Flowstart 0 0 0 1 Assignment 1 0..* 0..* 0..1 Addition 2..* 1 0..* 0..1 IsZero 1 0 0..* 0..2 GreaterZero 1 0 0..* 0..2 Delay 0 0 0..* 0..1

»  After a UML model of the desired functionality has been created it is required to configure the plugin parameters, so that the code generator and compiler can do their job. This is done in the configuration dialog available via menu "Tools/Options...". The following parameters have to /can be configured: Category Parameter Purpose Compiler C18 Compiler path Path to the C18 compiler executable, e.g. C:\MCC18\bin Compiler Include file path Path to the include files delivered with C18, e.g. C:\MCC18\h Linker C18 Linker path Path to the C18 linker executable, e.g. C:\MCC18\bin Linker C18 Library Path Path to the library files delivered with C18, e.g. C:\MCC18\lib Bootloader Start bootloader after build has finished If checked, the bootloader starts after successful code generation and compilation. Bootloader Download application automatically If checked, the download is done by the bootloader automatically as soon as a PIC running in bootload mode is detected at a USB port.

»  Finally the code generator is started using the menu "Tool/PIC/Generate code..." or the context menu of the diagram: