Finite State Machines With Input Multiplexing: A Performance Study

Abstract

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.Index Terms-Embedded memory blocks (EMBs), finite state machine (FSM), field programmable gate array (FPGA), logic synthesis, ROM.

FPGA Implementation of Reconfigurable Finite State Machine with Input Multiplexing Architecture Using Hungarian Method

“…It can be configured into a particular FSM in the set by applying the specific mode bits. Due to numerous advantages mentioned in the literature, FSMIM-S architecture [10] is chosen to implement the FSM (i.e., base ckt) part. Therefore, the Reconfigurable FSMIM-S architecture is constructed by combining the conventional FSMIM-S architecture [10] and multiplexer bank for mode based reconfiguration as shown in Figure 1.…”

“…The basic idea that has been implemented is to select only a specific set of inputs for a particular state. FSMIM with state-based input selection (FSMIM-S) is proposed in [10], which further reduces the ROM memory size.…”

“…The Reconfigurable FSMIM-S architecture is constructed by combining the conventional FSMIM-S architecture [10] and an optimized multiplexer bank (which defines the mode of operation). For this, the descriptions of a set of FSMs are taken for a particular application.…”

Hardware Reduction for Lut–Based Mealy FSMs

“…If (6) is violated, then an FSM circuit could be implemented as: (i) a network of EMBs or (ii) a network of LUTs and EMBs. A survey of various approaches to EMB-based design is provided by Garcia-Vargas and Senhadji-Navarro (2015). But these methods could be used only if there are "free" EMBs, which are not used for implementing other parts of a digital system.…”

High-Performance Architecture for Binary-Tree-Based Finite State Machines

“…For example, Xilinx asserts that large FSMs can be made more compact and faster by implementing them in EMBs [12]. In fact, cellbased implementations of large FSMs do not provide the best performance [13].…”