Question

9. Consider the following 4 bits to be stored in a memory with Hamming error correcting code. Assume even parity code. 1 0 0 a. Write the check bits. b. Assume when than an error changes one of the bits as follows. Can the error be detected and corrected/? 1

Answer 1

(a)

Therefore, Parity or check bits are 0, 0, 1.

P₂ 0 0 P₂ = 1 Number of is PO given four bits should be even. as even Parity, sum of Since, it is in a Circle or Hence, es = 0 P2 = 0 P3 -1.

(b)

dy del d3 0 0 0 1+0+0 to 21 0+1+0+0 = 1 0+0+0+ - detected Odd Parity detected odd Parity odd Parity detected NOT OK !

Error can be detected and corrected. Since the parity check for all three circles is failed, the bit that is corrupted is center bit i.e, d4 which can be corrected from 0 to 1.