On 6/7/23 15:13:29, Seymour J Metz wrote:
Given that the word length is a multiple of 4 bits, it is natural to group the data into groups of 4 bits, just as on 36 bit machines it was natural to group bits into groups of 3 and use octal notation. Add in the hexadecimal floating point and hex seems even more natural. The values 10 base 10 and 0A base 16 are the same, as is 1010 base 2, and which you use is purely a matter of convention and convenience.
After DEC had for a decade marketed 18-, 36-, and 12-bit machines with instruction fields that divided naturally(?) into multiples of 3 and (mostly) 6-bit characters, octal became the cultural imperative for representing computer data. Then came the 16-bit PDP-11 with 8-bit characters. IIRC, the initial cumbersome accommodation was to represent each octet as 3 octal digits with values from 000 to 377. -- gil
