Central Pattern generators (CPGs) are neural circuits that produce patterned signals to drive rhythmic behaviors in a robust and flexible manner. In this paper we analyze the triphasic rhythm of a well known CPG circuit using two different models of spiking-bursting neurons and several network topologies. By means of a measure of mutual information we calculate the degree of information exchange in the bursting activity between neurons. We discuss the precision and robustness of different network configurations.