Design a 4 bit serial adder Design a

Design a 4 -bit serial adder

What does this circuit do?

Can we simplify this circuit?

Simplified!

“i. Clicker” A state machine detects the sequences ‘ 0110, ’ ‘ 110, ’ and ‘ 011. ’ One of these sequences is redundant. Which two sequences do you need? A) 0110 and 110 B) 0110 and 011 C) 011 and 110

“i. Clicker” A state machine detects the sequences ‘ 0001, ’ ‘ 0111, ’ and ‘ 01. ’ One of these sequences is redundant. Which two sequences do you need? A) 0001 and 0111 B) 0001 and 01 C) 0111 and 01

Alternate Design Consideration Mealy Moore

Registers with load enable Load when L = 1 Maintain when L = 0 D 3 D 2 D 1 D 0

Registers with load enable Load when L = 1 Maintain when L = 0

Register Files

Data Destinations

Data Sources

Register File

fse 2 fse 1 fse 0 Operation 0 0 0 1 0 F = A+B F = A-B F = A+1 0 1 1 1 0 0 1 F=A F = A OR B F = A AND B 1 1 0 1 F = NOT A F = CLEAR DAe AAe BAe W fse 9 8 7 6 5 4 3 2 1 0

fse 2 fse 1 fse 0 Operation 0 0 0 1 0 F = A+B F = A-B F = A+1 0 1 1 1 0 0 1 F=A F = A OR B F = A AND B 1 1 0 1 F = NOT A F = CLEAR R 3←R 1 + R 2 DAe AAe BAe W fse

fse 2 fse 1 fse 0 Operation 0 0 0 1 0 F = A+B F = A-B F = A+1 0 1 1 1 0 0 1 F=A F = A OR B F = A AND B 1 1 0 1 F = NOT A F = CLEAR R 3←NOT A DAe AAe BAe W fse

fse 2 fse 1 fse 0 Operation 0 0 0 1 0 F = A+B F = A-B F = A+1 0 1 1 1 0 0 1 F=A F = A OR B F = A AND B 1 1 0 1 F = NOT A F = CLEAR DAe AAe BAe W fse

Matching Game MUX – Data inputs MUX – Selection inputs ALU – Function select inputs ALU – Data inputs DEC – Data outputs DEC – Enable bit ROM – Address bits ROM – Data bits ROM – Enable bit FSM – State bits FSM – Input bits FSM – Output bits REG File – Destination/source address bits REG File – Data out REG File – Write enable

Centrality of addressing