UTK - Math 171 - Alexiades

            ASCII


ASCII = American Standard Code for Information Interchange:
  • 128 (=27) character symbols encoded as 7-bit numbers
  • encodes 32 control codes (0–31 decimal) and 95 printable characters, for example:
    charDecimalHexOctalBinary 7bit
    NULL00000000 0000
    space3220040010 0000
    A6541101100 0000
    Z905A132101 1010
    @9660140110 0000
    a9761141110 0001
    z1227A172111 1010
    delete1277F177111 1111

  • ASCII was published as ASA X3.4-1963
  • first used commercially in 1963 as a seven-bit teleprinter code for AT&T TWX (TeletypeWriter eXchange)
  • ASCII was the common encoding on WWW till Dec 2007, then UTF-8
  • Unicode (UTF-8, UTF-16, UTF-32) vastly extends ASCII but starts with ASCII, so 7-bit codes match.
      It encodes more than 128,000 characters and symbols, covering 135 modern and ancient scripts,
      and Braille, and musical notation, and geometric shapes, and emoticons, and room for more!

  • ascii table (0-127) and extended ascii (128-255)
  • ascii conversions
  • unicode conversions