Set and reset Simulink

Hello,

I am having trouble regarding value holding and reset with a simulink function. When a condition occurs I would like to have that value held until an external reset occurs.

Ex)

if x==7
  z = 6; % but z stays at 6 even after x does not equal 7
elseif reset ==1 %reset occurs
  z = 0;
end

I would like to trigger a value, hold, use an external signal to reset, and then allow to trigger again. Is there a block that can do this?

Many thanks.

Answer 1

[Azzi Abdelmalek]

Try this

function z=fcn(x,reset)
persitent xx
if isempty(xx)
  xx=0
end
if (x==7|xx==1) & reset==0
  z = 6;
  xx=1;
elseif reset==1
  z = 0;
  xx=0
end

[Adam Keller]

In an S-function?

[Azzi Abdelmalek]

No, it's in Matlab function block

[Adam Keller]

That's what I meant, my apologies. Thank you Azzi!