Binary Codes Interview Question Answer

1	What are the different types of binary codes?
	Types of binary codes Numeric codes Alphanumeric codes
2	What is meant by alphanumeric code and numeric code?
	Alphanumeric code The alphanumeric code represents letters of alphabet and decimal numbers Numeric code The numeric code represents only numeric number i.e. 0 s and 1s
3	What is meant by BCD code?
	BCD code The full form of BCD is binary coded decimal. When numeric codes used to represent decimal digits are called as binary coded decimal codes.
4	Explain the term : Code word
	Code word It is a sequence of binary digits which represents a decimal digit.
5	Describe the different types of BCD code?
	BCD code Weighted code : ( 1 ) Positive weighted code and ( 2 ) Negative weighted code Non – weighted code
6	What is meant by weighted code and non – weighted code?
	Weighted code It is code in which each position of number has specific weight. Non – weighted code It is code in which each position of number does not obey weighted position principle.
7	What is meant by Positive weighted code and Negative weighted code?
	Positive weighted code It is code in which all the weights assigned to the binary digits are positive. The first weight must be 1 in all positive weighted code. The 4311, 3321 and 5211 are some of examples of positive weighted code. Negative weighted code It is a code in which at least one of the weights assigned to the binary digit is negative. The 642-3 and 84-2-1 is example of negative weighted code.
8	What is meant by sequential code?
	Sequential code It is a code in which each succeeding code word is one binary number greater than the preceding code word. The 8421 and XS – 3 code are example of sequential code.
9	Describe the condition for self complementing code.
	The given code is self complementing if the sum of the all weights of number is equal to 9. The 2421, 5211, 642 – 3, 84 – 2 – 1 are example of self complementing codes.
10	What is cyclic code?
	Cyclic code It is code in which each successive code word differs from the preceding one in only one bit position.
11	Which code is called as unit distant code? Give example
	Cyclic code The cyclic code is called as unit distant code because each successive code word differs from the preceding one in only one bit position. The Grey code is cyclic code.
12	Write one application of cyclic code.
	The cyclic code is used to translating an analog quantity of shaft position into digital quantity.
13	Why the 8421 BCD code is also called as naturally binary code?
	8421 BCD code The 8421 BCD code is also called as naturally binary code because 8,4, 2 and 1 weight is attached to it.
14	Describe the disadvantages of 8421 BCD code over binary code.
	Disadvantages of 8421 BCD code over binary code It require more bits as compared to that of binary code The binary addition and subtraction rules do not apply to the 8421 number but it is applicable only for group of 4 bits.
15	Describe the advantages of 8421 BCD code over binary code.
	Advantages of 8421 BCD code over binary code Ease of conversion in decimal number and vice versa
16	Describe the main difference between BCD code and 8421 BCD code.
	8421 BCD code The 8421 BCD code is simply as BCD code but each decimal digit is coded by 4 digit binary numbers in it.
17	Which are the illegal 8421 BCD codes? Why?
	There are 1010, 1011, 1100, 1101, 1110 and 1111 are illegal code because some of all weight of each code is greater than 9. 1010 = 8 + 0 + 2 + 0 = 10 1011 = 8 + 0 + 2 + 1 = 11 1100 = 8 + 4 + 0 + 0 = 12 1101 = 8 + 4 + 0 + 1 = 13 1110 = 8 + 4 + 2 + 0 = 14 1111 = 8 + 4 + 2 + 1 = 15
18	How the Excess 3 code is derives?
	The Excess 3 code is derives by addition of three 0011 to 8421 BCD code.
19	Which are the invalid states in the Excess 3 code? Why?
	There are following invalid state in the Excess 3 code because some of its weight is less than three or greater than 13 0000 = 0 + 0 + 0 + 0 = 0 0001 = 0 + 0 + 0 + 1 = 1 0010 = 0 + 0 + 1 + 0 = 2 1101 = 8 + 4 + 0 + 1 = 13 1110 = 8 + 4 + 2 + 0 = 14 1111 = 8 + 4 + 2 + 1 = 15
20	Why the Gray code is also called as cyclic code?
	Gray code The Gray code is also called as cyclic code because successive code words in this code differ in one bit position only.