bit-paired keyboard

bit-paired keyboard n. obs.  (alt. `bit-shift keyboard')
   A non-standard keyboard layout that seems to have originated with
   the Teletype ASR-33 and remained common for several years on early
   computer equipment.  The ASR-33 was a mechanical device (see
   {EOU}), so the only way to generate the character codes from
   keystrokes was by some physical linkage.  The design of the ASR-33
   assigned each character key a basic pattern that could be modified
   by flipping bits if the SHIFT or the CTRL key was pressed.  In
   order to avoid making the thing more of a Rube Goldberg kluge than
   it already was, the design had to group characters that shared the
   same basic bit pattern on one key.

   Looking at the ASCII chart, we find:

     high  low bits
     bits  0000 0001 0010 0011 0100 0101 0110 0111 1000 1001
      010        !    "    #    $    %    &    '    (    )
      011   0    1    2    3    4    5    6    7    8    9

   This is why the characters !"#$%&'() appear where they do on a
   Teletype (thankfully, they didn't use shift-0 for space).  This was
   *not* the weirdest variant of the {QWERTY} layout widely
   seen, by the way; that prize should probably go to one of several
   (differing) arrangements on IBM's even clunkier 026 and 029 card
   punches.

   When electronic terminals became popular, in the early 1970s, there
   was no agreement in the industry over how the keyboards should be
   laid out.  Some vendors opted to emulate the Teletype keyboard,
   while others used the flexibility of electronic circuitry to make
   their product look like an office typewriter.  These alternatives
   became known as `bit-paired' and `typewriter-paired' keyboards.  To
   a hacker, the bit-paired keyboard seemed far more logical -- and
   because most hackers in those days had never learned to touch-type,
   there was little pressure from the pioneering users to adapt
   keyboards to the typewriter standard.

   The doom of the bit-paired keyboard was the large-scale
   introduction of the computer terminal into the normal office
   environment, where out-and-out technophobes were expected to use
   the equipment.  The `typewriter-paired' standard became universal,
   `bit-paired' hardware was quickly junked or relegated to dusty
   corners, and both terms passed into disuse.