<hardware> (Obsolete, or "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
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.
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