Verbal Description of Coupled DEVS Behavior

The coupled DEVS's behavior is described verbally as follows.

1. When $N$ receives an input event, the coupled DEVS transmits the input event to the sub-components through the set of external input couplings.
2. When a sub-component produces its output event, the coupled DEVS transmits the output event to the other sub-components through the set of internal couplings. The coupled DEVS also produces an output event of $N$ through the set of external output couplings.

Example 2.2 (Ping-Pong Game)   Consider a ping-pong game with two players that each represented by the Player model introduced in Example 1.1 except the initial state.

Figure 1.3: DEVS Model of Ping-Pong Game

This block diagram can be modeled by a coupled DEVS such as $N_{PPGame}=<X,Y,D,\{M_i\},EIC, ITC, EOC>$ where $X=\{\};Y=\{\}; D$ ={A,B}; $\{M_i\}=$ {Player$_i$ } where Player$_i$ is the atomic DEVS introduced in Example 1.1 with initial states Send for $i$ =A, Wait for $i$ =B, respectively; $EIC$ ={ }, $ITC$ ={ (A.!send, B.?receive), (B.!send, A.?receive)}, $EOC$ = { }. $\square$