After you simulate your model using embedded types, and compare the floating point and fixed-point behavior of your system, determine if the new behavior is satisfactory. If the behavior of the system using the newly applied fixed-point data types is not acceptable, you can iterate through the process until you find settings that work for your system.
In the Convert Data Types section of the toolstrip, under the Settings menu, alter the proposal settings that the Fixed-Point Tool uses to generate data type proposals for objects in your system under design.
Click the Propose Data Types button to generate data type proposals using the new settings. After examining the new proposals in the spreadsheet, click the Apply Data Types button.
Simulate the model using the newly applied data types and compare the behavior as described in Verify New Settings. Continue to iterate through this process (edit proposal settings, propose data types, apply data types, verify system behavior) until you find settings for which your system's fixed-point behavior is acceptable.