Write the excess-3 equivalent codes of (6)10, (78)10 and (357)10

Write the excess-3 equivalent codes of (6)10, (78)10 and (357)10, all in 16-bit format.0011001100111001, 0011001110101011, 0011011010001010Determine the Gray code equivalent of (10011)2 and the binary equivalent of the Gray code number110011.A 16-bit data word given by 1001100001110110 is to be transmitted by using a fourfold repetitioncode. If the data word is broken into four blocks of four bits each, then write the transmitted bitstream.1001100110011001100010001000100001110111011101110110011001100110

The Correct Answer and Explanation is :

Let’s go step by step to clarify each of your queries.

Excess-3 Code (XS-3):

Excess-3 (XS-3) is a binary-coded decimal (BCD) code where each decimal digit is encoded by adding 3 (0011) to the binary representation of the digit. You provided decimal values (6), (78), and (357) and asked for the 16-bit Excess-3 equivalent.

  1. (6)₁₀ in Excess-3 (16-bit format):
  • First, we encode 6 using Excess-3 by adding 3 to it: (6 + 3 = 9), which in binary is 1001.
  • So, the Excess-3 code for 6 (in a 16-bit format) is 0000000000001001.
  1. (78)₁₀ in Excess-3 (16-bit format):
  • The first digit, 7, in Excess-3: (7 + 3 = 10) (binary 1010).
  • The second digit, 8, in Excess-3: (8 + 3 = 11) (binary 1011).
  • So, the Excess-3 code for 78 (in a 16-bit format) is 0000101000101011.
  1. (357)₁₀ in Excess-3 (16-bit format):
  • The first digit, 3, in Excess-3: (3 + 3 = 6) (binary 0110).
  • The second digit, 5, in Excess-3: (5 + 3 = 8) (binary 1000).
  • The third digit, 7, in Excess-3: (7 + 3 = 10) (binary 1010).
  • So, the Excess-3 code for 357 (in a 16-bit format) is 0000011000101000101010.

Gray Code:

Gray code is a binary numeral system where two successive values differ in only one bit. This encoding is used in various error correction applications because only one bit changes at a time.

  1. Gray code of (10011)₂:
  • The first bit (most significant) is the same in Gray code as in the original binary number. So the first bit of the Gray code is 1.
  • The subsequent bits of the Gray code are generated by XORing each pair of consecutive bits of the binary number:
    • Gray code bit 2: (1 \oplus 0 = 1)
    • Gray code bit 3: (0 \oplus 0 = 0)
    • Gray code bit 4: (0 \oplus 1 = 1)
    • Gray code bit 5: (1 \oplus 1 = 0)
  • Therefore, the Gray code equivalent of (10011)₂ is 11010.
  1. Binary equivalent of the Gray code 110011:
  • The first bit of the Gray code (most significant bit) is the same as the binary number: (1).
  • To decode, XOR each subsequent Gray code bit with the previous binary bit:
    • The first binary bit is 1.
    • The second binary bit: (1 \oplus 1 = 0)
    • The third binary bit: (0 \oplus 0 = 0)
    • The fourth binary bit: (0 \oplus 0 = 0)
    • The fifth binary bit: (0 \oplus 1 = 1)
    • The sixth binary bit: (1 \oplus 1 = 0)
  • So, the binary equivalent of Gray code 110011 is 100100.

Fourfold Repetition Code:

In a fourfold repetition code, each bit in the data is repeated four times to increase reliability. The given 16-bit data word is:

(1001100001110110)

To apply fourfold repetition, each 4-bit block is repeated four times. We break the 16-bit word into four 4-bit blocks:

  1. (1001 \rightarrow 1001 1001 1001 1001)
  2. (1000 \rightarrow 1000 1000 1000 1000)
  3. (1110 \rightarrow 1110 1110 1110 1110)
  4. (0110 \rightarrow 0110 0110 0110 0110)

Therefore, the transmitted bitstream is:

1001100110011001100010001000100001110111011101110110011001100110

Summary:

  • Excess-3 Code: We converted each decimal number into its corresponding Excess-3 code and formatted it in 16 bits.
  • Gray Code: We found the Gray code of a binary number and converted a Gray code back to binary.
  • Fourfold Repetition: We applied a fourfold repetition code to each 4-bit block of the data word, resulting in a longer but more redundant transmission for error detection.

This explains the conversions and the steps in detail! Let me know if you have further questions.

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