meta bit

2 definitions found

meta bit - Free On-line Dictionary of Computing (26 May 2007) :

  meta bit
  
     The top bit of an 8-bit character, which is on in character
     values 128--255.  Also called high bit, alt bit, or
     hobbit.  Some terminals and consoles (see space-cadet keyboard
     ) have a META shift key.  Others (including,
     *mirabile dictu*, keyboards on IBM PC-class machines) have an
     ALT key.  See also bucky bits.
  
     Historical note: although in modern usage shaped by a universe
     of 8-bit bytes the meta bit is invariably hex 80 (octal
     0200), things were different on earlier machines with 36 bit
     words and 9-bit bytes.  The MIT and Stanford keyboards (see
     space-cadet keyboard) generated hex 100 (octal 400) from
     their meta keys.
  
     [Jargon File]
  

meta bit - Jargon File (4.4.4, 14 Aug 2003) :

  meta bit
   n.
  
     The top bit of an 8-bit character, which is on in character values
     128--255. Also called high bit, alt bit. Some terminals and
     consoles (see space-cadet keyboard) have a META shift key. Others
     (including, mirabile dictu, keyboards on IBM PC-class machines) have
     an ALT key. See also bucky bits.
  
     Historical note: although in modern usage shaped by a universe of
     8-bit bytes the meta bit is invariably hex 80 (octal 0200), things
     were different on earlier machines with 36-bit words and 9-bit bytes.
     The MIT and Stanford keyboards (see space-cadet keyboard) generated
     hex 100 (octal 400) from their meta keys.