User manual MATLAB SIMULINK FIXED POINT RELEASE NOTES

[. . . ] Simulink® Fixed PointTM Release Notes How to Contact The MathWorks Web Newsgroup www. mathworks. com/contact_TS. html Technical Support www. mathworks. com comp. soft-sys. matlab suggest@mathworks. com bugs@mathworks. com doc@mathworks. com service@mathworks. com info@mathworks. com Product enhancement suggestions Bug reports Documentation error reports Order status, license renewals, passcodes Sales, pricing, and general information 508-647-7000 (Phone) 508-647-7001 (Fax) The MathWorks, Inc. 3 Apple Hill Drive Natick, MA 01760-2098 For contact information about worldwide offices, see the MathWorks Web site. Simulink® Fixed PointTM Release Notes © COPYRIGHT 2002­2010 by The MathWorks, Inc. The software described in this document is furnished under a license agreement. The software may be used or copied only under the terms of the license agreement. [. . . ] Fixed Bugs and Known Problems Bug Reports Includes fixes Related Documentation at Web Site No New features and changes introduced in this version are · "New Signal Logging Options in the Fixed-Point Tool" on page 34 · "Add, Subtract, and Sum Blocks Use an Accumulator Data Type" on page 34 · "Cast Operations with Net Bias Use an Intermediate Data Type" on page 35 · "Non-Matrix-Wise Parameter Scaling Modes Removed" on page 35 New Signal Logging Options in the Fixed-Point Tool In this release, the Fixed-Point Tool includes new options that provide batch control of signal logging for models and subsystems. These options allow you to enable or disable logging for multiple signals simultaneously, based on the location of signals in a model hierarchy and whether the signals have names. For more information, see the documentation for the fxptdlg function in the Simulink Reference. Add, Subtract, and Sum Blocks Use an Accumulator Data Type In previous releases, the Add, Subtract, and Sum blocks used a user-specified output data type to perform all operations. This behavior might have caused precision loss and saturation during intermediate operations, producing unexpected results. In this release, these blocks use an ideal accumulator data type when performing intermediate operations. Consequently, the 34 Version 5. 5 (R2007b) Simulink® Fixed PointTM Software Add, Subtract, and Sum blocks now produce more precise results, and the Real-Time Workshop product generates less saturation code for them. Cast Operations with Net Bias Use an Intermediate Data Type Data type conversions with net bias involve an intermediate addition operation. In previous releases, blocks that perform such casts used the output data type's container to compute the addition operation. This behavior might have caused extra saturation, producing unexpected results. In this release, data type conversions can use an ideal data type when performing all intermediate operations. By reducing or eliminating intermediate saturations, cast operations now produce more accurate results, and the Real-Time Workshop product generates more efficient code for them. Non-Matrix-Wise Parameter Scaling Modes Removed In previous releases, the Gain and Weighted Moving Average blocks contained a parameter named Parameter scaling mode whose options included the following scaling modes: · Best Precision: · Best Precision: · Best Precision: · Best Precision: Element-wise Row-wise Column-wise Matrix-wise In this release, only the Best Precision: Matrix-wise setting is available, and it is now simply named Best precision. On the Parameter Attributes pane of the Gain or Weighted Moving Average block parameter dialog box, use the Data Type Assistant to specify Best precision for the Scaling control. Compatibility Considerations Pre-R2007b models that contain Gain or Weighted Moving Average blocks whose Parameter scaling mode option specifies a non-matrix-wise setting will be updated automatically when loaded in R2007b. That is, the Simulink software will change non-matrix-wise settings to Best precision, which now 35 Simulink® Fixed PointTM Release Notes represents matrix-wise-best-precision scaling. Consequently, affected blocks might generate results that differ from those obtained in previous releases. 36 Version 5. 4. 1 (R2007a+) Simulink® Fixed PointTM Software Version 5. 4. 1 (R2007a+) Simulink Fixed Point Software This table summarizes what's new in Version 5. 4. 1 (R2007a+): New Features and Changes No Version Compatibility Considerations No Fixed Bugs and Known Problems Bug Reports Includes fixes Related Documentation at Web Site No 37 Simulink® Fixed PointTM Release Notes Version 5. 4 (R2007a) Simulink Fixed Point Software This table summarizes what's new in Version 5. 4 (R2007a): New Features and Changes Yes Details below Version Compatibility Considerations No Fixed Bugs and Known Problems Bug Reports Includes fixes Related Documentation at Web Site No New features and changes introduced in this version are Fixed-Point Tool The Fixed-Point Tool is a new interactive graphical environment for analyzing and scaling fixed-point systems, which replaces the Fixed-Point Settings interface in previous releases. To access the tool, from the Simulink model editor Tools menu, select Fixed-Point Settings. Alternatively, you use the fxptdlg function to access the tool. See "Fixed-Point Tool" in Simulink Fixed Point User's Guide for a tutorial that demonstrates how to use the new interface. 38 Version 5. 3 (R2006b) Simulink® Fixed PointTM Software Version 5. 3 (R2006b) Simulink Fixed Point Software This table summarizes what's new in Version 5. 3 (R2006b): New Features and Changes Yes Details below Version Compatibility Considerations No Fixed Bugs and Known Problems Bug Reports Related Documentation at Web Site No New features and changes introduced in this version are Fixed-Point Enhancements in Simulink Blocks This section describes enhancements to fixed-point data type support in Simulink blocks. Math Function Block The sqrt operation in the Math Function block supports fixed-point data types. New Lookup Table Blocks The new Prelookup and Interpolation Using Prelookup blocks support fixed-point data types. 39 Simulink® Fixed PointTM Release Notes Version 5. 2. 1 (R2006a+) Simulink Fixed Point Software This table summarizes what's new in Version 5. 2. 1 (R2006a+): New Features and Changes No Version Compatibility Considerations No Fixed Bugs and Known Problems Bug Reports at Web site Related Documentation at Web Site No 40 Version 5. 2 (R2006a) Simulink® Fixed PointTM Software Version 5. 2 (R2006a) Simulink Fixed Point Software This table summarizes what's new in Version 5. 2 (R2006a): New Features and Changes Yes Details below Version Compatibility Considerations No Fixed Bugs and Known Problems Bug Reports at Web site Related Documentation at Web Site No New features and changes introduced in this version are · "Fixed-Point Block Parameters Supported" on page 41 · "'Simplest' Rounding Mode" on page 41 Fixed-Point Block Parameters Supported This release allows you to specify fixed-point numbers as the values of Simulink block parameters. In particular, you can specify fixed-point data types in Simulink block parameter dialog boxes and as values of the data type property of Simulink. Parameter objects. See "Configuring Blocks with Fixed-Point Parameters" for more information. 'Simplest' Rounding Mode A new Simplest rounding mode is available for the Round integer calculations toward parameter of some fixed-point Simulink blocks. This rounding mode attempts to reduce or eliminate the need for extra rounding code in your generated code. The Simplest rounding mode is currently available for the following blocks: · Data Type Conversion · Product · Lookup Table · Lookup Table (2-D) · Lookup Table Dynamic 41 Simulink® Fixed PointTM Release Notes For more information, refer to "Rounding Mode: Simplest" in the product documentation. 42 Version 5. 0 (R14) Simulink® Fixed PointTM Software Version 5. 0 (R14) Simulink Fixed Point Software This table summarizes what's new in Version 5. 0 (R14): New Features and Changes Yes Details below Version Compatibility Considerations Yes--Details labeled as Compatibility Considerations, below. Fixed Bugs and Known Problems Yes Details Related Documentation at Web Site No New features and changes introduced in this version are · "Product Restructuring" on page 43 · "Fixed-Point Blocks Fully Integrated into Simulink Software" on page 44 · "API for User-Written Fixed-Point S-Functions" on page 52 · "Fixed-Point Advisor" on page 52 · "Arithmetic with Non-Zero Bias Fully Supported" on page 52 · "Generated Code for Lookup Tables Uses Less ROM" on page 53 · "Functions Moved to Simulink Software" on page 53 · "Obsolete Functions" on page 54 · "Major Bug Fixes" on page 54 Product Restructuring The Fixed-Point Blockset has been replaced by two new products, Fixed-Point ToolboxTM and Simulink Fixed Point. This product restructuring reflects the broad expansion of fixed-point capabilities in the MATLAB and Simulink software. [. . . ] All the functionality from each original block has been maintained in unifying these blocks. Compatibility with fixed-point data types and/or specific fixed-point features are now available with all of these blocks, whether the blocks used are from the Simulink library or the Fixed-Point Blockset library. You do not need to make any changes to your earlier models as a result of this improvement. You can now use any of the unified blocks with either built-in data types or fixed-point data types, which eliminates the need to replace blocks in your models when you want to use different data types. [. . . ]