User`s guide

Upgrading from an Earlier Release
3-15
additive signals). This resulted in an implicit delay. Now you must explicitly
define the delay by inserting a memory block.
Improved Invalid Model Configuration Diagnostics
This version of Simulink does a better job of detecting and flagging invalid
modeling constructs in Simulink models. Consequently models that ran in
previous versions of Simulink (sometimes producing incorrect results) may not
run in the current release. The changes include:
•Direct feedthrough compensation no longer occurs by default for S-functions
(see “Direct Feedthrough Compensation Deprecated” on page 3-13).
•S-functions are now sorted like built-in blocks (see “S-Functions Sorted Like
Built-In Blocks” on page 3-14).
•Simulink no longer inserts implicit latches in triggered subsystems that
directly or indirectly trigger themselves (see “Self-Triggering Subsystems
Are No Longer Allowed” on page 3-14, above). Instead it signals an error
when it detects a triggered subsystem loop with unlatched inputs. To avoid
the error, you must select the
Latch option on the triggered subsystem’s
input ports.
•Simulink now signals an error when it detects invalid configurations of
function-call subsystems. See the Subsystem Examples block in the
Subsystems library for examples of illegal modeling constructs involving
function-call subsystems. You can disable this diagnostic by setting the
Invalid FcnCall Connection parameter on the Diagnostics pane of the
Simulation Parameters dialog box to none or warning.