This paper introduces the Discrete Dithered Desynchronization (D3sync) algorithm which is a decentralized Time Division Multiple Access (TDMA) technique in which a set of network nodes computes iteratively a conflict-free schedule so that each node obtains a portion of a frame that is an integer multiple of a fixed slot size. The algorithm is inspired by the dynamics of Pulse Coupled Oscillators (PCO), but unlike its predecessors that divide arbitrarily the frame among the nodes in the network, the D3sync allocates discrete resources among the network nodes. Our paper proves the convergence of the D3sync algorithm and gives an upper bound on the convergence time of the algorithm.