tailieunhanh - Lecture Digital logic design - Lecture 23: More Sequential Circuits Analysis

Lecture 23 More Sequential Circuits Analysis. The main contents of the chapter consist of the following: Discussed more sequential circuit analysis, state machines models, moore and mealy model comparison, mixed model, examples. | Lecture 23 More Sequential Circuits Analysis Give qualifications of instructors: DAP teaching computer architecture at Berkeley since 1977 Co-athor of textbook used in class Best known for being one of pioneers of RISC currently author of article on future of microprocessors in SciAm Sept 1995 RY took 152 as student, TAed 152,instructor in 152 undergrad and grad work at Berkeley joined NextGen to design fact 80x86 microprocessors one of architects of UltraSPARC fastest SPARC mper shipping this Fall Analysis of Combinational Vs. Sequential Circuits Combinational : Boolean Equations Truth Table Output as a function of inputs Sequential : State Equations State Table State Diagram Output as a function of input and current state Next state as a function of inputs and current state. Analysis of Sequential Circuits Steps: Obtain state equations FF input equations Output equations Fill the state table Put all combinations of inputs and current states Fill the next state and output Draw the state diagram State Table The time sequence of inputs, outputs, and flip-flop states can be enumerated in a state table. Table consists of four sections labeled present state. input. next state. and output Derivation of a state table consists of first listing all possible binary combinations of present state and inputs. Clocked Sequential Circuit Analysis (State Table) Clocked Sequential Circuit Analysis (State Table) A sequential circuit with m flip-flops and n inputs needs (2m+n -1) rows in the state table. 2 FF and 1 in put so (23 – 1) = 7, as counting starts from 0 => 0-7 so ABx starts from 000 till 111. Clocked Sequential Circuit Analysis (State Diagram) Graphical representation of State Table State is represented by a circle Transition between states is indicated by directed lines connecting the circles 1/0, 1/1, 0/0, 0/1 are input/output A directed line connecting a circle with itself indicates that no change of state occurs State table is easier to derive from a given logic . | Lecture 23 More Sequential Circuits Analysis Give qualifications of instructors: DAP teaching computer architecture at Berkeley since 1977 Co-athor of textbook used in class Best known for being one of pioneers of RISC currently author of article on future of microprocessors in SciAm Sept 1995 RY took 152 as student, TAed 152,instructor in 152 undergrad and grad work at Berkeley joined NextGen to design fact 80x86 microprocessors one of architects of UltraSPARC fastest SPARC mper shipping this Fall Analysis of Combinational Vs. Sequential Circuits Combinational : Boolean Equations Truth Table Output as a function of inputs Sequential : State Equations State Table State Diagram Output as a function of input and current state Next state as a function of inputs and current state. Analysis of Sequential Circuits Steps: Obtain state equations FF input equations Output equations Fill the state table Put all combinations of inputs and current states Fill the next state and output Draw the