Breakpoint in Simulink MATLAB function block not working

I add a breakpoint to the code in my MATLAB function block in Simulink. I am running Simulink from a script using sim and it does not stop at the breakpoint. It is running the function because Simulink errors are being generated from functions called by the function block.

Answer 1

[Scott]

I tried a breakpoint in a similar model and it worked. I then realized that the function is not running; my Simulink error is a coder error.

Answer 2

[Fangjun Jiang]

Try sim("modelName","Debug","on")?

https://www.mathworks.com/help/simulink/slref/sim.html

[Scott]

Did not work.

[Fangjun Jiang]

Then it is better to run simulation interactively to debug it, although you could use sldebug().