Fixed-Point Blockset

Compatibility with Simulink Blocks

You can connect built-in Simulink blocks directly to Fixed-Point Blockset blocks provided the signals use built-in Simulink data types. The built-in data types include uint8, uint16, uint32, int8, int16, int32, single, double, and boolean. The Fixed-Point Blockset supports all built-in data types. However, a fixed-point signal consisting of 8-, 16-, or 32-bit integers is compatible with built-in Simulink blocks only when its scaling is given by a slope of 1 and a bias of 0.

Some Simulink blocks impose restrictions on the data type of the signals they can handle. For example, some Simulink blocks only accept doubles. To incorporate these blocks into your fixed-point model, you must configure the driving block(s) to use doubles.

Note    If you want to connect Simulink blocks that only handle built-in data types to Fixed-Point Blockset blocks that output blockset-specific data types, then you must use the Gateway Out or Conversion block to convert to a built-in data type.

Some Simulink blocks can accept signals of any data type. For these blocks, you can input any of the built-in data types or any of the blockset-specific data types. Examples of blockset-specific data types include 32-bit signed integers with a scaling of 2^-8, and 18-bit unsigned integers with a scaling of 2⁰.

In some cases, fixed-point signals that are not built-in data types are converted to a real-world value as it enters the block. For example, the To Workspace block will output a 32-bit signed integer with a scaling of 2^-8 as a double.

Refer to the Simulink documentation for detailed information about the data types handled by each Simulink block.

The Development Cycle

Unified Simulink and Fixed-Point Blockset Blocks