Moore) - Mallard Intro to Computer Engineering I - HWK #8...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
HWK #8 Solution Problem 8.0 (a) In a 8-bit ripple adder, C 1 is calculated after 3 units of time. After that every C i is calculated in C i-1 + 2 units of time. So C 7 is calculated in 3+(2*6)=15 units of time. To calculate S 7 , it takes 15+1 = 16 units of time. (The 1 unit is the delay for the last FA) In the CSA shown in the diagram, S 7 is calculated after C 4 is calculated (we have to add the MUX delay) C 4 is calculated in 3+(2*3) = 9 units of time. Adding the MUX delay, we calculate S 7 in 9+3 = 12 units of time. Problem 8.0 (b) The P/G is calculated in 1 unit of time, carries in 2 units and the FA delay is 1 unit. The total latency is 1+2+1 = 4 units of time for a 8-bit CLA. If we use Carry Select as shown above, each of the 4-bit CLA will have a latency of 4 units of time (1+2+1 as explained above). The MUX will have a latency of 3 units. So the total latency is 4+3 = 7 units of time Problem 8.0 (c) MUX delay does not change. Carry Select is faster as N increases. Problem 8.0 (d) LHS Expression Boolean property used C8,0 * 1 + C4 * C8,1 Identity C8,0*(C8,1 + C8,1') + C4*C8,1 Complementarity C8,0*C8,1 + C8,0*C8,1' + C4*C8,1 Distributive C8,0*C8,1 + 0 + C4*C8,1 Apply C8,0' + C8,1 = 1 C8,0*C8,1 + C4*C8,1 Identity C8,1*(C8,0+C4) Distributive Problem 8.1 Problem 8.2 (a) The next-state table is shown below, and the state diagram to the right. Current State
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/21/2011 for the course ECE 290 taught by Professor Staff during the Spring '08 term at University of Illinois, Urbana Champaign.

Page1 / 6

Moore) - Mallard Intro to Computer Engineering I - HWK #8...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online