Sometimes, as the functionality of a block changes, the change cannot be made without breaking the behaviour the model expects of the block. For instance, when a block has a couple of options replaced by a single option, the block cannot adjust itself when the model loads, and Simulink will print a series of error messages.

When this kind of change occurs, rather than change the existing block, a new block is created with the new functionality, while the old block is retained as is. This allows the model to load without Simulink printing errors and the model can be changed to use the new block as required.

However, to remove old functionality over time, the old block will be removed in a future version of the developer software, ensuring the blockset remains efficient. Blocks which are to be removed in the future are marked deprecated, and the documentation for those blocks indicates how to replace the block with an equivalent block that isn't marked deprecated.

Currently, the following blocks are marked deprecated and will be removed in a future version of the developer software. Please replace the use these blocks as soon as possible.