Consider the following asynchronous system consisting of $G_1$ and $G_2.$

$\backslash$table$[[$bool $x_1$:$=0,,$bool $x_2$:$=0,],[A_{x_1}$:$,x_1$:$=not{x}_1,y_1,A_{y_1}^{\text{'}}$:$x_2=1x_2$:$=not{y}_1,y_2$