Re: PDP-11 compat mode [was Re: New Vax - future directions :-)]

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

>>>>               C <- {borrow into most significant bit};
>>>>               C <- {borrow out of most significant bit};
>>> You're correct; the description you cited is an obvious typo.
>> A nigh-ubiquitous one!  [...]
> Not sure if it is a typo, or if it is a question on how you interpret
> it.

> With substraction, you actually am borrowing into the most
> significant bit, and that is what the carry indicates.  That a
> borrowing was needed.

But it's a borrow out of that bit, not into it.

At least, as I learnt to use the terms, and as they are used elsewhere
in the VARM (eg, when describing carries in addition; I see no reason
why the meanings of "into" and "out of" would be switched between
carries and borrows).

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