I could have asked this question on
https://retrocomputing.stackexchange.com but it is likely too linguistic for that forum (they don't have a terminology tag), and still could be too hackerish for this one:
Is there (or was there when programming was done at a lower level than today, and required more bit-twiddling) a tendency in colloquial professional English to convert the phrase "all ones" that denotes a bit pattern within a computer register or a memory location consisting of all "1" bits, into a noun?
For the opposite, all zeros, the common form is simply "a zero", but I have never heard "all ones" elevated to a noun phrase that could take an article.
A bit of trivia: in Russian, the corresponding word was "всеед" (vseed), shortening of "все единицы" (vse edinitsy, 'all ones'), incidentally homonymous to the word with the meaning "pantophage".