ECE 09241 Lecture Notes - Critical Path Method, Metastability, Sequential Logic

• School: Rowan University
• Department: Electrical and Computer Engineering
• Course: ECE 09241

Document Summary

Intro to digital systems course notes: lecture 7. A moore action appears in an fsm"s state, as in the fsms seen in earlier sections. In contrast, a mealy action appears on an fsm"s transition. In other words, a moore action"s output value is a function of the present state, while a mealy action"s output value is a function of the present state and present input values. In general, mealy actions may have the benefit of capturing some behaviors using fewer states, and of having output values change immediately in response to input value changes. However, mealy actions also have the drawback of possible glitches on outputs, of no guarantee that an output value will last at least one clock cycle, and potential timing problems if multiple circuits fsms are connected. A solution to these problems is to place a flip-flop at each output, though that delays output updates by a clock cycle.