User`s guide

Building Models
2-7
Building Models
You can use IQmath Library blocks in models along with certain core
Simulink, Fixed-Point Blockset, and other blockset blocks. This section
discusses issues you should consider when building a model with blocks from
these different libraries.
Converting Data Types
As always, it is vital to make sure that any blocks you connect in a model have
compatible input and output data types. In most cases, IQmath Library blocks
handle only a limited number of specific data types. You can refer to any block
reference page in “Block Reference” for a discussion of the data types that the
block accepts and produces.
When you connect IQmath Library blocks and Fixed-Point Blockset blocks, you
often need to set the data type and scaling in the block parameters of the
Fixed-Point Blockset block to match the data type of the IQmath Library block.
Many Fixed-Point Blockset blocks allow you to set their data type and scaling
through inheritance from the driving block, or through backpropagation from
the next block. This can be a good way to set the data type of a Fixed-Point
Blockset block to match a connected IQmath Library block.
Some DSP Blockset blocks and core Simulink blocks also accept fixed-point
data types. Make the appropriate settings in these blocks’ parameters when
you connect them to an IQmath Library block.
Using Sources and Sinks
The IQmath Library does not include source or sink blocks. Use source or sink
blocks from the core Simulink library or Fixed-Point Blockset in your models
with IQmath Library blocks.
Choosing Blocks to Optimize Code
In some cases, blocks that perform similar functions appear in more than one
blockset. For example, both the IQmath Library and the Fixed-Point Blockset
have a Multiply block. When you are building a model to run on C2000 DSP,
choosing the block from the IQmath Library always yields better optimized
code. You can use a similar block from another library if it gives you