This paper presents one approach to design logic control systems using event-condition-action (ECA) rules implemented with IEC 61499 function blocks (FBs). ECA rules have been used extensively to specify the behavior of active database and expert systems and are recognized as a highly reconfigurable tool to design reactive behavior. Recent results have shown how the use of ECA rules can greatly increase the modularity, integrability, and diagnosability of the logic control system thus increasing its reconfigurability. This paper proposes a FB architecture such that the behavior of the control system follows the ECA paradigm.