Question

Write out the result of separately performing each of the two assembly commands: complement and negate on the following register values.

a.0x2a

b.0x7d

Answer 1

Ans) complement instruction per forms one's complement and negate instruction performs 2's complement i.e one's complement+1

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a) 0x2a =0x0010 1010

result after complement instruction is(complement each bit )i.e 0x 1101 0101=0xd5

result is 0xd5

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result after negate instruction is (2's complement i.e 1's complement+1)

i.e 0x 1101 0101(calculated above ) +1=0x1101 0110=0xd6

result is 0xd6

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b)

a) 0x7d =0x0111 1101

result after complement instruction is(complement each bit )i.e 0x 1000 0010=0x82

result is 0x82

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result after negate instruction is (2's complement i.e 1's complement+1)

i.e 0x 1000 0010(calculated above ) +1=0x1000 0011=0x83

result is 0x83

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