EGR 2400 EXAM 1 2025 QUESTIONS AND
ANSWERS
How do you convert from decimal to binary? - ANS divide the decimal number by increments
of 2, the binary number will be the remainders of the divisions taken from the bottom up
how do you convert from a decimal (base 10) to an octal number? - ANS divide by 8 and take
the remainders
(divide the decimal number by the base you want to convert to)
hexadecimal numbers - ANS 0-9, A, B, C, D, E, F
A= 10
B=11
C= 12
D= 13
E= 14
F = 15
what does the MSB (most significant bit) of a number represent? - ANS 0: positive
1: negative
1's Complement - ANS MSB = 0: the number is positive
the remaining n-1 bits represent the magnitude
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, MSB = 1: the number is negative
the remaining n-1 bits do not represent the magnitude
to change the sign- invert all the bits
2's Complement - ANS MSB = 0: the number is positive and the remaining n-1 bits represent
the magnitude
MSB = 1, the number is negative, and the remaining n-1 bits DO NOT represent the magnitude
-to change the sign, invert all the bits and add 1 to the LSB
gray code - ANS allows only one bit to change between successive numbers
BCD code - ANS binary coded decimal
-encoding scheme that encodes using the 4 bit binary equivalent
in a multiple input AND gate, what happens to an open input and why? - ANS an open input
will float high
-if it does not float high, then the open input will automatically make the output go low
XOR gate - ANS outputs a 1 when exactly one input is a 1
-inputs must be different to output a high
"wink detector"
XNOR - ANS outputs a high when the inputs are equal
two lows or two highs produce a high
how can gates be implemented in real life? - ANS switches
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ANSWERS
How do you convert from decimal to binary? - ANS divide the decimal number by increments
of 2, the binary number will be the remainders of the divisions taken from the bottom up
how do you convert from a decimal (base 10) to an octal number? - ANS divide by 8 and take
the remainders
(divide the decimal number by the base you want to convert to)
hexadecimal numbers - ANS 0-9, A, B, C, D, E, F
A= 10
B=11
C= 12
D= 13
E= 14
F = 15
what does the MSB (most significant bit) of a number represent? - ANS 0: positive
1: negative
1's Complement - ANS MSB = 0: the number is positive
the remaining n-1 bits represent the magnitude
Copyright ©2025 BRIGHTSTARS ALL RIGHTS RESERVED 1
, MSB = 1: the number is negative
the remaining n-1 bits do not represent the magnitude
to change the sign- invert all the bits
2's Complement - ANS MSB = 0: the number is positive and the remaining n-1 bits represent
the magnitude
MSB = 1, the number is negative, and the remaining n-1 bits DO NOT represent the magnitude
-to change the sign, invert all the bits and add 1 to the LSB
gray code - ANS allows only one bit to change between successive numbers
BCD code - ANS binary coded decimal
-encoding scheme that encodes using the 4 bit binary equivalent
in a multiple input AND gate, what happens to an open input and why? - ANS an open input
will float high
-if it does not float high, then the open input will automatically make the output go low
XOR gate - ANS outputs a 1 when exactly one input is a 1
-inputs must be different to output a high
"wink detector"
XNOR - ANS outputs a high when the inputs are equal
two lows or two highs produce a high
how can gates be implemented in real life? - ANS switches
Copyright ©2025 BRIGHTSTARS ALL RIGHTS RESERVED 2
