so-un-bot/0721_6/wrong2.txt

0;
end System;


2.

class System
Real x; // MB in buffer
Real u; // input pulse
initial equation
x = 3;
u = 0;
equation
when sample(0, 1) then
  u = 1 - pre(u);
end when;
der(x) = 2*u - 1.0;
end System;