ERROR DETECTION AND CORRECTION Pablo Barrac Asi, ECE, MEng
Data Communications Code • Data communications codes are often used to represent character and symbols, such as letters, digits and punctuation marks. Therefore, data communications codes are called character codes, character sets, symbol codes, or character languages.
Binary Information Codes MORSE CODE The first datacom code with three unequal length symbols. Table of Morse Code
Binary Information Codes BAUDOT CODE The first fixed-length character code. It is a 5 bit character code, with a start bit and a 1.5 stop bits. Jean-Maurice-Emile Baudot
Binary Information Codes AMERICAN STANDARD CODE FOR INFORMATION INTERCHANGE (ASCII) it uses 7 bits of information, an 8 th bit for use as parity, a start bit and two stop bits
Binary Information Codes EXTENDED BINARY CODE DECIMAL INTERCHANGE CODE (EBCDIC) the true 8 level code
Error Detection and Correction Techniques • ERROR DETECTION The process of monitoring the received data and determining when a transmission error has occurred.
Error Detection 1. REDUNDANCY - involves transmitting each character twice. If the same character is not received 2x in succession, an error has occurred - retransmission of the entire message is very inefficient, because second transmission of a message is 100% redundant
- Fall '19
- ASCII, Error detection and correction, Parity bit