The behavior of two pacemakers simulated by integrate and fire oscillators reciprocally connected by synapses is studied. The activation of each synapse produces a sudden potential shift in the post-synaptic neuron. Two sorts of behaviour may occur when at least one synapse is excitatory. Phase-locking occurs for almost every set of parameters, and given certain initial conditions. Repetitive patterns in indifferent equilibrium appear in the presence of a given set of parameters and certain other initial conditions. Quasi-periodic behaviour corresponds to almost every set of parameters when both synapses are inhibitory, although repetitive patterns of firing in indifferent equilibrium occassionally occur.