The memory model was created for use by client programs for Noda's soccer server [Noda1995]. The server provides a virtual field and simulates the motion of two teams of players and the ball. The players are controlled by separate client programs which connect to the server using UDP/IP sockets. The simulator also provides an interface for a coach, which can move and monitor the players to provide a facility for testing. This paper discusses the details of the client's interface to the server, since this determines the inputs to the memory model and the actions the client has available. The model described in this paper is designed and tested using version 1.x of the simulator. A newer version of the simulator, 2.x, has been made available. The differences in the sensory information provided by the two versions are given in this section. Calculations necessary to extend the memory model are provided in the appendix.