The paper concerns the problem of stale assignment for finite stale machines (FSM), tar-geting at PAL-based CPLDs implementations. Presented in the paper approach is dedicated to stale encoding of fast automata. The main idea is to determine the number of logic levels of the transition function before the stale encoding process, and keep the constraints during the process. The number of implicants of every single transition function must be known while assigning states, so elements of two level minimization based on Primary and Secondary Merging Conditions are implemented in the algorithm. The method is based on code length extraction if necessary. In one of the most basic stages of the logic synthesis of sequential devices, the elements referring to constraints of PAL-based CPLDs are taken into account.