Input as delays for temporal logic (Stateflow)

Hello,

I have a Stateflow chart with many temporal logic transitions. It uses fixed step solver with 0.2 step size. I use integer numbers 1, 2 to represent delays

after(1, sec)

When I use only integer numbers as delays, everything works fine. But after I decided to apply delay as an integer input of a chart

after(delay1, sec)

(Delay1 is integer input of chart) I receive the message:

The following expression contains non-integer code. The option 'Support
floating-point numbers' has not been set in Code Generation configuration
options. Hence, only integer code/data is allowed.

Transition #1 in Chart 'Logic' (#2): after(delay1, sec)[..]

So, if I check an option 'Support floating-point numbers' the compiled code size bloats because of floating point math. How could I set delays as int inputs and get rid from floating point math? Thank you.

Answer 1

[Corey Lagunowich]

You can specify that the data type of input delay1 is an integer type, either in the Property Inspector or by using the Stateflow API.

Note that using a (possibly) varying threshold like this can lead to non-intuitive results. For example,

1. At time t = 1, State "Off" is entered. It is guarded by an outgoing transition "after(delay1,sec)". At t = 1, the value of delay1 is 10.
2. At time t = 9, the value of delay1 changes to 2. The after() operator is now evaluated as true, and State Off is exited after 8 seconds instead of 10. But, of course, it was also exited much later than had the threshold been 2 seconds to begin with.