Discrete Mathematics Practical 8 Page 1 of 2 Oliver Hyde Practical 8: Parity Builder A parity bit, or check bit, is a bit added to a string of binary code to ensure that the total number of 1-bits in...

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Discrete Mathematics Practical 8 Page 1 of 2 Oliver Hyde Practical 8: Parity Builder A parity bit, or check bit, is a bit added to a string of binary code to ensure that the total number of 1-bits in the string is even or odd. Parity bits are used as a simple form of error detection. If an odd number of bits (including the parity bit) are transmitted incorrectly, the parity bit will be incorrect, thus indicating that a parity error occurred in the transmission. The parity bit is only suitable for detecting errors; it cannot correct any errors, as there is no way to determine which particular bit is corrupted. Parity bit checking is sometimes used for transmitting ASCII characters, which have 7 bits, leaving the 8th bit as a parity bit. Even parity: the parity checking circuit counts the number of 1-bits and adds the parity bit to make the total number of 1-bits an even number. Prepare a Parity Builder spreadsheet (an example template is shown below). Steps involved: ❑ The user is prompted to enter a single character. ❑ Calculate the ASCII code for the character in decimal. ❑ Convert the ASCII code for the character to binary (note that ASCII codes have seven bits). ❑ Separate the binary form into its seven component bits. ❑ Calculate the parity bit using even parity (parity bit = sum of component bits mod 2). ❑ The ASCII code for transmission is the 8-bit code (7-bit ASCII code + parity bit as shown in template). https://en.wikipedia.org/wiki/Bit https://en.wikipedia.org/wiki/Binary_code https://en.wikipedia.org/wiki/Even_number https://en.wikipedia.org/wiki/Odd_number https://en.wikipedia.org/wiki/Transmission_(telecommunications) https://en.wikipedia.org/wiki/Error_detection_and_correction https://en.wikipedia.org/wiki/ASCII Discrete Mathematics Practical 8 Page 2 of 2 Oliver Hyde Important Excel functions: • CODE(text). • DEC2BIN(number, [places]). • MID(text, start_num, num_chars). • MOD(number, divisor). Spreadsheet protection Ensure your spreadsheet is protected (so users cannot corrupt it), no password, with only user input cells having unlocked protection. Submitting your Answers ❑ Create a single Excel spreadsheet named as follows: the word Practical, followed by a space and the practical number, i..e. Practical 8. ❑ Submit the spreadsheet via Moodle by Friday before 11:55 p.m. You may only submit once. Late submissions are not permitted.