> On 9 Feb 2017, at 13:12, Michael Kjörling <michael at kjorling.se> wrote:
> 
> On 8 Feb 2017 17:50 -0500, from ron at ronnatalie.com (Ron Natalie):
>> Amusingly in the UNIVAC FIELDDATA character set.   The @ had the value zero
>> (and was called the master space).
> 
> That wouldn't have anything to do with how ^@ is a somewhat common
> representation of 000, would it? (Yes, using octal on purpose.) I've
> always kind of wondered where that notation came from.
> 
> That ^A through ^Z were representations of 001 through 032 makes more
> sense.

Isn’t it because it is simply the control code + 0100 to arrive at the
capitals column of the ascii table? (http://www.asciitable.com)

Hence ^@ for NULL and ^[ for ESC.