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* History of data encodingAs discussed last time, one of the fundamental requirements for a code set to be useful in WAN communications is that the sender and the receiver must agree on the meaning of each combination of ones and zeros. A 2-bit code set, for example, can have only four discrete meanings: one meaning each for the combinations 00, 01, 10, and 11. Go to three bits and you get eight codes; four bits yield 16, and five bits yield 32. The first widely accepted code set was Baudot code, developed more than 100 years ago. By having five bits - and 32 code combinations - there were enough bit combinations available to have a unique code for each of the 26 letters of the alphabet. However, 26 letters plus the 10 digits 0 through 9 exceed the 32 combinations. Rather than going to an additional bit, two unique codes are used to signal a shift between the "letters" interpretation of the code and the "figures" interpretation. Since both "letters" and "figures" tend to come in groups, this works fine for simple applications. However, there's one big problem. With just five bits, there's no way to distinguish between UPPERCASE and lowercase letters. Going to a 6-bit code with 64 combinations would still be minimal, because it would take 62 combinations for the letters and digits, with only two codes left for punctuation. Consequently, the minimal code set must consist of seven bits, and that's exactly what the American Standard Code for Information Interchange (ASCII) uses. This code, which has become the de facto standard for data communications, has 128 combinations, with a unique code for each letter in both uppercase and lowercase. In fact the binary code for each uppercase and lowercase letter is the same except for one bit, which is sometimes called the "shift" bit. Learn more about this topicSOS @morse.codeNetwork World Convergence Newsletter, 03/03/04 IETF ponders internationalized e-mailNetwork World ISP News Report Newsletter, 11/24/03 Industry group to promote internationalized domain namesNetwork World ISP News Report Newsletter, 12/01/03 ASCII art generatorNetwork World Q&A: Dunn discusses comeback of NortelNetwork World, 03/08/04 Join the Network World communities on Facebook and LinkedIn to comment on topics that are top of mind. Copyright © 2004 IDG Communications, Inc. 1a. What is the minimum number of bits that are required to uniquely represent the characters of English alphabet? (Consider upper case characters alone) The number of unique bit patterns using i bits is 2i We need at least 26 unique bit patterns. The cleanest approach is to compute log2 26 and take the ceiling .This yields 5 as the answer. Trial and error is also an acceptable solution. 1b. how many more characters can be uniquely represented without requiring additional bits? With 5 bits, we can represent up to 32 (25) unique bit patterns; we can represent 32 - 26 = 6 more characters without requiring additional bits. 2 Using 7 bits to represent each number, write the representations of 23 and -23 in signed Magnitude and 2's complement integers.
Answer & Explanation Solved by verified expert <p>a molestie consequat, ultrices ac magna. Fusce dui lectus, congue vel laoreet ac, dictum vitae odio. Donec aliquet. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam lacinia pulvinar tortor nec facilisis. Pellentesque dapibus efficitur laoreet.</p> Fusce dui lectus, congue vel laoreet ac, dictum vitae odio. Donec aliquet Unlock full access to Course Hero Explore over 16 million step-by-step answers from our library Subscribe to view answer sque dapibus efficitur laoreet. Nam risus ante, dapibus a molestie consequat, ultrices ac magna. Fusce dui lectus, congue vel laoreet ac, dictum vitae odio. Donec aliq usce dui lectus, congue vel laoreet ac, dictum vitae odio. Donec aliquet. Lorem ipsum dolongue vel laoreet ac, dictum vitae odio. Donec aliquet. Lorem ipsum dolor sit amet, consectetur adipiscing et, consectetur adipiscing elit. Nam lac F gue vel laoreet ac, dictum vitae odio. Donec aliquet. Lorem ipsum dolor sit amet, consectetur adipiscing e nec facilisis. Pellentesque dapibus Fusce dui lFusce dui lFusce dui lsFusce dui lFusce dui lFusce dui lsFusce dui lFusce dui lFusce dui ls
l How many bits are needed to represent the A letters of the alphabet?If you want to represent one character from the 26-letter Roman alphabet (A-Z), then you need log2(26) = 4.7 bits. Obviously, in practice, you'll need 5 bits.
How many bits would be needed to count all of the students in the alphabet?5 bits (2^5) gives you 32 unique values, which is enough unique values to hold the alphabet and a space.
What is the average number of bits required to encode a character?In ASCII, every character is encoded with the same number of bits: 8 bits per character.
How many ways are there to encode the 260,1}; 2^8=256 it results that we have Arrangements taken 26 with 256 elements.
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