If you actually look at the ascii chart broken out by bitfield you’ll see that the codes and key tops reflect a tight mapping (remember old teletypes were electromechanical: an electric motor drove the platen but all the keystroke decoding was mechanical. The usual ascii chart (e.g. man ascii) obscures this by using hex or decimal codes.)
So they had a block of 31 control character (forget null, and delete obviously wasn’t in there because of paper tape).
Many of those control characters were and are useful (^s for stop, ^r for resume) much of the space was empty and so randomly assigned. There would have been room for more bell characters, but that wasn’t really the mentality of the day.
So they had a block of 31 control character (forget null, and delete obviously wasn’t in there because of paper tape).
Many of those control characters were and are useful (^s for stop, ^r for resume) much of the space was empty and so randomly assigned. There would have been room for more bell characters, but that wasn’t really the mentality of the day.