Finite state machines with input multiplexing (FSMIMs)
have been proposed in previous works as a technique for efficient
mapping FSMs into ROM memory. In this paper, we propose a new
architecture for implementing FSMIMs, called FSMIM with state-based
input selection, whose goal is to achieve a further reduction in memory
usage. This paper also describes in detail the algorithms for generating
FSMIMs used by the tool FSMIM-Gen, which has been developed
and made available on the Internet for free public use. A comparative
study in terms of speed and area between FSMIM approaches
and other field programmable gate array-based techniques is presented.
The results show that the FSMIM approaches obtain huge
reductions in the look-up table (LUT) usage by using a small number
of embedded memory blocks. In addition, speed improvements
over conventional LUT-based implementations have been obtained in
many cases