Ptolemy Tutorial

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Ptolemy Tutorial

• What is Ptolemy?
• How it works?
• What is the development environment for you
• Show demo and former simulation work

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What is Ptolemy

• Ptolemy is a software infrastructure (kernel)
  developed by EECS dept, Berkeley
• Object-oriented
• Support modeling, simulation, design and code
  generation for concurrent, embedded real-time
  system.
• Support multiple domains
• Support heterogeneous environment

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Organization of the software
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Domains in Ptolemy
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Ptolemy executables

• Pigi
• All domains and targets plus GUI
• Ptrim
• SDF,BDF,DDF,DE,CGC and HOF domains plus GUI
• Ptiny
• SDF and DE domains plus GUI
• Ptcl
• All domains, no GUI

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Basic building bocks
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NamedObj
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Basic building blocks

• Star lowest level block in Ptolemy, with
  functionality defined in c
• Galaxy A block consisting of sub-blocks with
  input and output.
• Universe An outmost block defining a executable
  system
• Domain A model of computation, defining the
  behavior of a network of objects
• Wormhole A galaxy with different domains from
  inside and outside

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Domain classes derived
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Block communication
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Hierarchical Abstraction
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Hierarchical Abstraction (cont)
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Star definition
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Star definition (cont)
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DE model

• Provides a generic environment for time-oriented
  simulation system
• Queuing system
• Communication network
• High-level modeling of computer architecture
• Particles represent event change of system state

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DE model

• Each particle has an associated timestamp
• A global event queue sorts events by timestamp
• DE processes event in a chronological order
  (fetches the first one)

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DE model (cont.)
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File organization
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Setup your environment

• Environment variables
• PTOLEMY full path name of ptolemy installation
• PTARCH the platform on which Ptolemy is running
• Setup environment (put in .cshrc)
• setenv PTOLEMY ptolemy
• setenv PTARCH PTOLEMY/bin/ptarch
• setenv path (PTOLEMY/bin PTOLEMY/bin.PTARCH
  path)

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Setup environment (cont.)

• On machines in cs dept
• View available module
• Module ptolemy
• Load Ptolemy
• Module load soft/ptolemy
• Setup JAVAHOME environment variable
• setenv JAVAHOME /soft/java/SunOS5.6/JDK-1.3

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Running Ptolemy

• Run Ptolemy demo
• Go to demo directory
• cd PTOLEMY/demo
• Run pigi
• Run former simulation
• FC-AL
• SSA
• XOR-based disk

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Using GUI

• Programs
• Vem
• Oct
• pigiRPC
• Design objects
• Oct design manager and database
• Facet a design object(schematic or palette)
• Schematic a design block diagram
• Palette a facet containing a library of icons

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Sample code for FC-AL

• LPSM
• Input
• Inbound (from the loop)
• fromFC2 (FC-2 layer)
• Output
• Outbound (to the loop)
• toFC2 ( to upper layer)

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LPSM

• Internal states
• State (int)
• AL_PA (int)
• Fairness (int)
• progDelay (float)
• transTime (float)

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LPSM implementation

• Methods
• Setup
• Go
• wrapup

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Checklist to write your own simulation system

• Have a overview of Ptolemy
• Conduct Architectural design of your system
• Basic star
• Galaxy
• Universe
• Get familiar with the Ptolemy running
  environment, draw the schematic diagram
• Implement all your stars
• Tweak and run your simulation
• Analyze the result

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New direction of Ptolemy

• Ptolemy II
• Java based simulation environment

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Resources

• http//ptolemy.eecs.berkeley.edu

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Resources

• User Manual
• Pigi
• Ptcl
• Domains
• Vem
• Pxgraph
• installation

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Resources (cont.)

• Programmer manual
• Software organization
• Writing stars
• Infrastructure
• Data types
• tcl/tk
• Domains
• Code generation

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Resources (cont.)

• Kernel manual
• All stars defined in kernel
• Targets used in kernel