ASCII characters, including those from the extended ASCII character sets, are stored in memory as 8-bit bytes. Each ASCII character has a unique 7-bit binary code, with values ranging from 0000000 (0 in decimal) to 1111111 (127 in decimal). When storing an ASCII character in memory, the 7-bit binary code is placed in a byte with the most significant bit (MSB) set to 0, effectively making it an 8-bit value.
Extended ASCII character sets, such as ISO-8859-1 (Latin-1) or Windows-1252 (CP1252), use the full capacity of an 8-bit byte to represent 256 unique characters instead of just 128. When storing extended ASCII characters in memory, each character is represented by an 8-bit byte, just like the original ASCII characters. The 8-bit representation allows for the full range of 256 characters, including both the original ASCII characters (0 to 127) and the extended characters (128 to 255).
For example, the letter 'A' has an ASCII value of 65, which corresponds to the 7-bit binary code 1000001. When storing this character in memory, the binary code is placed in an 8-bit byte with the MSB set to 0: 01000001. In the case of an extended ASCII character like 'Ñ' in the ISO-8859-1 character set, it has a decimal value of 209, which corresponds to the 8-bit binary code 11010001.
When processing or transmitting text data, computer systems and communication protocols use these byte representations of ASCII and extended ASCII characters to encode, store, and transfer information. However, due to the lack of standardization among extended ASCII character sets, compatibility issues may arise when transferring data between systems that use different character sets.An ASCII character is a character from the American Standard Code for Information Interchange (ASCII) character set. The ASCII character set consists of 128 characters, including 33 non-printable control characters and 95 printable characters. The printable characters include English letters (uppercase and lowercase), digits (0-9), punctuation marks, and some common symbols, such as the space character.
ASCII characters are represented by 7-bit binary numbers, with each character having a unique binary code ranging from 0000000 (0 in decimal) to 1111111 (127 in decimal). These codes are used to store, process, and transmit text data in computer systems and across various communication protocols.ASCII is limited to 128 characters because it was designed to use 7-bit binary numbers for encoding. With 7 bits, you can represent 2^7, or 128, unique values. The decision to use 7 bits was mainly based on the technical limitations and requirements of the time when ASCII was developed in the 1960s.
During that period, computer systems and communication protocols were less advanced and needed simpler, more compact encoding schemes. By using a 7-bit encoding, ASCII could be easily stored and transmitted over early telecommunication systems. The 128 characters in ASCII were sufficient to represent the most commonly used characters in English text and some control characters for basic communication and formatting tasks.