  Let $\Phi:\{0,1\}^{n}\longrightarrow\{0,1\}^{n}$. The asynchronous flows are
(discrete time and real time) functions that result by iterating the
coordinates $\Phi_{i}$ independently on each other. The purpose of the paper is
that of showing that the asynchronous flows fulfill the properties of
consistency, composition and causality that define the dynamical systems. The
origin of the problem consists in modelling the asynchronous circuits from the
digital electrical engineering.
