Hi everyone,

I am working on an adapter for virtual commissioning using ModelingToolkit.jl. More specifically, I use discrete callbacks (timed → periodic) to read inputs from and write output to a soft-controller. Is there a way to set the `initial_affect`

and the `final_affect`

arguments from DiffEqCallbacks.jl using ModelingToolkit.jl? Here is my MWE:

```
using ModelingToolkit, DifferentialEquations
using ModelingToolkit: t_nounits as t, D_nounits as D
function affect!(integ, u, p, ctx)
println("Time: $(integ.t)")
end
@mtkmodel SimpleSystem begin
@parameters begin
m = 1.0
end
@variables begin
y(t) = 0.0
end
@equations begin
D(y) ~ m
end
@discrete_events begin
1 => (affect!,[],[],[],nothing)
end
end
@mtkbuild sys = SimpleSystem()
prob = ODEProblem(sys, Pair[], (0, 10.0))
sol = solve(prob)
```

If you run this code the event will not be triggered for t = 0.0 nor 10.0. If explicitly add additional events like this:

```
@discrete_events begin
[0,10] => (affect!,[],[],[],nothing)
1 => (affect!,[],[],[],nothing)
end
```

both events will be called twise. I guess this is related to the solver starting at some \Delta t in the first case (and thus overstepping 0.0) and being forced to start with 0.0 in the second case. Is there currently a way arround this behavior in ModelingToolkit.jl?