Question

EE252 100 Points Digital Design I Two's Complement Subtraction and Add / Subtract Circuits Homework 3. (25 Pts) The following circuit uses two 7483 (4-bit adder) ICs, labeled 7483-1 and 7483-2, respectively. Answer the questions for EACH of the following THREE CASES: Case 1: D=0010, and E = 0110 Case 2: D = 1000, and E = 0101 Case 3: D = 1000, and E = 1001 a. (6 Pts - 2 Pts per Case) What are the binary inputs applied to the inputs A1, A3, Az. Ai, B., B3, B2, and B, of the second 4-bit adder (7483-2)? b. (6 Pts - 2 Pts per Case) What are the outputs labeled X, Y, Z and the binary output for SA , , and of the second 4-bit adder (7483-2)? c. (3 Pts) What purpose does C. of the first 4-bit adder, contribute to the circuit? Explain. ES DE DE, DE, D. Bo A B A B2 A2 7483-1 Σ. B. A cm Σ. Σ. BA B A B Ą 7483-2 B. A d. (10 Pts) Explain What Function is being performed by this circuit and How the circuit performs that function.

Answer 1

ES DE 902 EO E Bu Au Hg P3 By A₂ BY AI bu Au BzA3 B2 Az " 7463- ). Eu E; Er D = 0010 D: 1000 E=0101 E: 0110 O) 1000 BBB, B, D- 1000 E -1001 00001 Bu B3 & B, cin 1101 Bu BBB - Cin + B4 (83+B 2= 0+1(1) = 1 + 0 =1 Za 0+0=0 13-1 TE=1] 12:0] → A4 Agf, A, = 0000 Ay AAA - 0110 Aut AA2A, = 0110 Bu By B, B1 = 1000 l BubaBB, = 1101 | Bu B3RB, = 0001

let the first ulit adoler (72183-3) ocet probe instead of Eu E E2E, are sus; S, S, 5 x = $2+ Sa y = Su (Sa+S3) z = Cours) et Su (Sz+ S3) - Cout +Y COURO Caso care D: 1000 020010 D-1000 E-1001 E-0110 E-001 ssss. = 110 Su SS, S, = 1000 Couto S.SS.S, : 0001 Coute = 1 Cauti = 0 x=0 0 X=1 0 Y1 Z- 6+1 z1+0 E=1 Z= 0+0 [2:07 Susass = 0001 Au Ą A₂4, ollo Su5,5,5, = 1000 AAAA, - 0000 11000 SS8.5 = 1101 AAAA = 0110 DOO) T0119 Cout ELS & - 1000 Exce$ - 001 &&&&-0111

acecalley cutpeet in representing in 4 butku then maximam range of u bits in 0 to 15. •) Canti Cu = 1. when sum of 15 Of digite are digite care » Coute = Cu=0 ; when sum of digits are <15 o) from equcation of z Z: C4 + Y to 1 is added C4 = 9 0110 when adder. Second - from the 3 cases in the below problems a&b. when the carry is occur of Y=1 then olio is adding * Yi Su (E3+23) - Su($3+54) - Em (10,11,12,13,14,15) knowing from this result it cleanley a) sum is above 9 . tum is above 15 on Cuocur

result. finally giving Ol10 rescelt in in odding the to BCD. Care 3: case 1: care 2 : D=8 D-8 0:2 E = 6 E-9 From these three cases BCD operation B is performed. so this circent in the u-bit BCO adder. Brief: → 7 Ow! + co boce 1000 0101 1101 ollo + 0011 I[3 4 bit added result.