# Detect and Correct Errors in Modified Error-Correcting Hamming Code

• needhelp83
In summary, a 16-bit word is stored in the main memory using modified error correcting Hamming code. When read by a program, the word is analyzed by the error correcting hardware, which calculates new parity bits based on specific bits in the word. However, upon comparison, one of the calculated parity bits does not match the expected value, raising the question of whether this is a correct result or if there are suggestions for improvement.
needhelp83
A 16-bit word is coded in modified error correcting Hamming code and after that is stored into a cell of the main memory. After some time a program reads the cell and the following word is read into the memory data register:

0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 1 0 1 1 1 1 1

Perform all operations, which the error correcting hardware does to analyze the word and to detect/correct the possible error.

0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 1 0 1 1 1 1 1
21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Pall

Pnew1 = CW1 + CW3 + CW5 + CW7 + CW9 + CW11 + CW13 + CW15 + CW19 + CW21=
1+ 1 + 0 + 1 + 0 + 0 + 0 + 0 + 0 + 0=1

Pnew2 =CW2 + CW3 + CW6 + CW7 + CW10 + CW11 + CW14 +
CW15 + CW18+ CW19=
1+ 1 + 1 + 1 + 0 + 0+ 0+0+ 1+0=1

Pnew3= CW4 + CW5 + CW6 +CW7 + CW12 + CW13 + CW14 +
CW15 + CW20+ CW21=
1+ 0+1 + 1+ 0+ 0+ 0+ 0+ 0+0=1

Pnew4= CW8 + CW9 +CW10 +CW11 + CW12 + CW13 +CW14+ CW15=
0+ 0 +0 + 0+0 + 0 + 0+ 0=0

Pnew5= CW16 + CW17 +CW18 + CW19 + CW20 +CW21 =
0 + 0 +1 + 0 +0 + 0=1

Pallreceived is equal to Pallcalc, but the Pnew5 doesn't equal to "0" at position 16 which it should. So, would this be correct or not?

Any suggestions?

Based on the calculations, it seems that there may be an error in the data at position 16. The error correcting hardware should have corrected this error, but it is possible that the error was too severe for the hardware to correct. Further analysis would be needed to determine the exact cause of the error and if it can be corrected. However, it is important to note that the error correcting Hamming code is designed to detect and correct errors, but it is not foolproof and some errors may still occur.

## 1. How does the modified error-correcting Hamming code work?

The modified error-correcting Hamming code works by adding extra bits to a data stream in order to detect and correct errors that occur during transmission. These extra bits are calculated based on the binary value of the data bits, and are used to check for errors when the data is received. If an error is detected, the code is able to determine which bit was incorrect and correct it.

## 2. What types of errors can the modified error-correcting Hamming code detect and correct?

The modified error-correcting Hamming code is able to detect and correct single-bit errors, as well as some multiple-bit errors. It is also able to detect and flag any uncorrectable errors, so that the data can be retransmitted if necessary.

## 3. How is the modified error-correcting Hamming code different from traditional Hamming codes?

The modified error-correcting Hamming code differs from traditional Hamming codes in that it uses a more complex algorithm to calculate the extra bits, allowing it to detect and correct a wider range of errors. It also utilizes a parity check matrix, which helps to identify and correct errors more efficiently.

## 4. Is the modified error-correcting Hamming code always successful in correcting errors?

No, the modified error-correcting Hamming code is not always successful in correcting errors. It is designed to detect and correct errors, but there are certain scenarios where it may not be able to do so. For example, if there are too many errors in the data stream, the code may not be able to determine which bits are incorrect and therefore cannot correct them.

## 5. How is the performance of the modified error-correcting Hamming code measured?

The performance of the modified error-correcting Hamming code is typically measured by its error-correcting capability, which is the maximum number of errors that it can detect and correct. This capability is often compared to the minimum number of errors that would cause the code to fail, known as the code's minimum distance. A higher error-correcting capability and minimum distance indicate a more reliable code.

• Engineering and Comp Sci Homework Help
Replies
7
Views
929
• Engineering and Comp Sci Homework Help
Replies
7
Views
2K
• Engineering and Comp Sci Homework Help
Replies
5
Views
2K
• Engineering and Comp Sci Homework Help
Replies
7
Views
2K
• Programming and Computer Science
Replies
4
Views
700
• Nuclear Engineering
Replies
7
Views
642
• Engineering and Comp Sci Homework Help
Replies
6
Views
2K
• Engineering and Comp Sci Homework Help
Replies
1
Views
2K
• Set Theory, Logic, Probability, Statistics
Replies
1
Views
916
• Programming and Computer Science
Replies
9
Views
1K