Digital Logic GATE Question Answers with Explanation.
Q1 – Let R1 and R2 be two 4-bit registers that store numbers in 2’s complement form. For the operation R1+R2, which one of the following values of R1 and R2 gives an arithmetic overflow? (GATE 2022)
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R1 = 1011 and R2 = 1110
R1 = 1100 and R2 = 1010
R1 = 0011 and R2 = 0100
R1 = 1001 and R2 = 1111
Ans – (2)
Explanation –
Q2 – Consider a digital display system (DDS) shown in the figure that displays the contents of register X. A 16-bit code word is used to load a word in X, either from S or from R. S is a 1024-word memory segment and R is a 32-word register file. Based on the value of mode bit M, T selects an input word to load in X. P and Q interface with the corresponding bits in the code word to choose the addressed word.
Which one of the following represents the functionality of P, Q, and T? (GATE 2022)
P is 10:1 multiplexer; Q is 5:1 multiplexer; T is 2:1 multiplexer
P is 10:210 decoder; Q is 5:25 decoder; T is 2:1 encoder
P is 10:210 decoder; Q is 5:25 decoder; T is 2:1 multiplexer
P is 1:10 de-multiplexer; Q is 1:5 de-multiplexer; T is 2:1 multiplexer
Ans – (3)
Explanation –
Q3 – Consider three floating point numbers A, B and C stored in registers RA, RB and RC, respectively as per IEEE-754 single precision floating point format. The 32-bit content stored in these registers (in hexadecimal form) are as follows.
RA= 0xC1400000 Â Â RB = 0x42100000 Â Â RC = 0x41400000
Which one of the following is FALSE? (GATE 2022)
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A + C = 0
C = A + B
B = 3C
(B – C) > 0
Ans – (2)
Explanation –Â