fxptdlg

Start Fixed-Point Tool

Syntax

fxptdlg('modelname')

Description

fxptdlg('modelname') starts the Fixed-Point Tool for the Simulink^® model specified by modelname. You can also access this tool by the following methods:

• From the Apps tab, under Code Generation click Fixed-Point Tool.

• From a subsystem context (right-click) menu, select Fixed-Point Tool.

In conjunction with Fixed-Point Designer™ software, the Fixed-Point Tool provides convenient access to:

• Model and subsystem parameters that control the signal logging, fixed-point instrumentation mode, and data type override.

• Plotting capabilities that enable you to plot data that resides in the MATLAB^® workspace, namely, simulation results associated with Scope, To Workspace, and root-level Outport blocks, in addition to logged signal data (see Signal Logging (Simulink))

• An interactive automatic data typing feature that proposes fixed-point data types for appropriately configured objects in your model, and then allows you to selectively accept and apply the data type proposals

You can launch the Fixed-Point Tool for any system or subsystem, and the tool controls the object selected in its System under design pane. If Fixed-Point Designer software is installed, the Fixed-Point Tool displays the name, data type, design minimum and maximum values, minimum and maximum simulation values, and scaling of each model object that logs fixed-point data. Additionally, if a signal saturates or overflows, the tool displays the number of times saturation or overflow occurred.

Note

If your model uses accelerator or rapid accelerator simulation modes, the Fixed-Point Tool changes the simulation mode to normal during range collection, and then sets it back to its original simulation mode once the range collection simulation is complete.

Overriding Fixed-Point Specifications

Most of the functionality in the Fixed-Point Tool is for use with the Fixed-Point Designer software. However, even if you do not have Fixed-Point Designer software, you can configure data type override settings to simulate a model that specifies fixed-point data types. In this mode, the Simulink software temporarily overrides fixed-point data types with floating-point data types when simulating the model.

Note

If you use fi objects or embedded numeric data types in your model or workspace, you might introduce fixed-point data types into your model. You can set fipref to prevent the checkout of a Fixed-Point Designer license.

To simulate a model without using Fixed-Point Designer:

1. Enter the following at the command line.

   set_param(gcs, 'DataTypeOverride', 'Double',...
    'DataTypeOverrideAppliesTo','AllNumericTypes',...
    'MinMaxOverflowLogging','ForceOff')

2. If you use fi objects or embedded numeric data types in your model, set the fipref DataTypeOverride property to TrueDoubles or TrueSingles (to be consistent with the model-wide data type override setting) and the DataTypeOverrideAppliesTo property to All numeric types.

   For example, at the MATLAB command line, enter:

    p = fipref('DataTypeOverride', 'TrueDoubles', ...
   		'DataTypeOverrideAppliesTo', 'AllNumericTypes');