Simulink Release Notes

Bug Fixes

This section lists fixes to bugs that occurred in the previous version of Simulink.

• Variable sample time S-functions

• Simulink no longer crashes when an S-function with variable sample time is placed in an atomic subsystem.

• Bus selector detection of duplicated names

• A bug related to the detection of a duplicated name in a bus that was feeding a Bus Selector block was fixed.

• Optimize block memory use

• In Simulink 4.0, the Continuous and Discrete Transfer Function blocks and the Discrete Filter block used more memory than they needed to, particularly for the case of many poles. They now use an optimal amount of memory.

• Miscellaneous fixes to the model loader

• Miscellaneous bug fixes have been performed on the model loader:
  • The loader and saver now retain any comment lines (i.e., lines that begin with #) that are found at the top of the model file.
  • The loader does not crash on Windows NT when file sizes are integer multiples of 4096.
  • The loader does not hang on corrupt models in which blocks with duplicate names are found.

• Profiler fixes

• The Simulink profiler now saves its files in the temporary directory. See the MATLAB command tempdir. The help was also updated.

• Chirp block fix

• The Chirp block now sweeps through frequencies correctly from the initial frequency at the simulation start time to the target frequency at the target time.

• Function-call subsystem bug fixes

• This version fixes several bugs related to the execution orders of function-call subsystems.

• Sorting bug fix

• Previous versions incorrectly computed the direct feedthrough setting for nonvirtual subsystems in triggered/function-call subsystems. This resulted in incorrect execution (sorting) orders. Now all nonvirtual subsystems within triggered subsystems have their direct feedthrough (needs input) flags set for all input ports. This is needed because a nonvirtual subsystem with a triggered sample time executes both its output and update methods together within the context of the model's output method.

• Fixed handling of grounded/unconnected inputs feeding certain blocks

• Simulink 4.0 incorrectly handled grounded or unconnected inputs to level-1 and level-2 S-functions requiring contiguous inputs and to some Matrix blocks. This has been fixed in Simulink 4.1.

Block Library

Upgrading from an Earlier Release