Stateflow® and Stateflow® Coder Release Notes

Chapter 6
Stateflow 5.1 and Stateflow Coder 5.1 Release Notes

New Features

This section introduces features and enhancements added in Stateflow 5.1 and Stateflow Coder 5.1 (which are available via Web download) since the release of Stateflow 5.0 (the Release 13 CD).

Truth Tables

Stateflow now provides a concise and powerful mechanism to represent Truth Tables as part of a state diagram. Truth tables provide the convenience of specifying functions with the logical behavior in a tabular form without having to draw flow graphs.

Because they are implemented on top of Stateflow graphical functions, Stateflow truth tables provide the following functionality to users:

• Truth tables are callable from anywhere on the chart
• Truth tables can call other truth tables
• Truth tables can access all of chart data (inputs, outputs, locals)
• Truth tables can broadcast events into Simulink

Stateflow provides its own analysis and diagnostics for underspecified and overspecified truth tables and fully integrates truth tables into the Stateflow Debugger and the Simulink/Stateflow Model Coverage tool.

Truth tables are introduced in the online release of Stateflow 5.1 and are documented in Truth Tables in Stateflow online documentation.

New RTW/Custom Target Coder Options

Stateflow provides users with the following four new options for generating code for Real-Time Workshop (RTW) and custom targets:

• Compact nested if-else using logical AND/OR operators -- Improves readability of generated code by compacting nested if-else statements using logical AND (&&) and OR (||) operators.
• Recognize if-elseif-else in nested if-else statements -- Improves readability of generated code by recognizing and emitting an if-elseif-else construct in place of deeply nested if-else statements.
• Replace constant expressions by a single constant -- Improves readability by preevaluating constant expressions and emitting a single constant. Furthermore, this optimization opens up opportunities for eliminating dead code.
• Minimize array reads using temporary variables -- In certain microprocessors, global array read operations are more expensive than accessing a temporary variable on stack. Using this option minimizes array reads by using temporary variables when possible.

These coder options are new for Stateflow version 5.1 and are documented in RTW Target (rtw) Coder Options in Stateflow online documentation.

Code Generation Speed Improved

Major Bug Fixes

© 1994-2005 The MathWorks, Inc.