SIXBIT
From Computer History Wiki
SIXBIT is a predecessor encoding system to ASCII; it too supported encoding various glyphs (written forms such as letters, numbers, etc) in 6 bits (hence the name); it only supported upper-case characters, however. SIXBIT contains the characters with ASCII codes from 32 to 95; to get the SIXBIT code for one of these characters, simply subtract 32 from the ASCII code.
It allowed 6 characters to be carried in the then-common 36-bit words common on many computers; with 18-bit and 12-bit computers then being common also, it had wide utility.
The values (given in octal, the usual binary-friendly base used on the computers on which SIXBIT was used) were:
| High | .0 | .1 | .2 | .3 | .4 | .5 | .6 | .7 |
|---|---|---|---|---|---|---|---|---|
| 0. | ' ' | ! | " | # | $ | % | & | ' |
| 1. | ( | ) | * | + | , | - | . | / |
| 2. | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| 3. | 8 | 9 | : | ; | < | = | > | ? |
| 4. | @ | A | B | C | D | E | F | G |
| 5. | H | I | J | K | L | M | N | O |
| 6. | P | Q | R | S | T | U | V | W |
| 7. | X | Y | Z | [ | \ | ] | ^ | _ |
