You can view a list of blocks that support fixed-point design in documentation by filtering the blocks reference list. Click Blocks right below the blue bar at the top of the Help window, then select the Fixed-Point Conversion check box at the bottom of the left column under Extended Capability. The blocks are listed in their respective categories. You can use the table of contents in the left column to navigate between the categories. Refer to the Extended Capabilities > Fixed-Point Conversion section of each block page for any notes and limitations.
To obtain this filtered list for DSP System Toolbox™, click Blocks that Support Fixed-Point Design.
Alternatively, you can find this information in the Simulink® block data type support table for the DSP System Toolbox. To access this table, type this command in the MATLAB® Command Window.