Many thanks Bruce that makes it perfectly clear.
@Alain Thanks too. Apologies for mentioning the "C" letter BTW!
As for the RTFM thing. Please, it's a cop out. It's the easiest thing in the world to belittle someone for not finding the information (or quite understanding how to frame a question) you may think should be obvious, but in the context of the wider picture may not be to the person asking the question. And of course the "Problem" may only be one of several or several tens that the poster may be concurrently dealing with at the time of the question.
Sorry Alain, I really don't mean to appear to be negative after you've been kind enough to reply to my question, it's just that RTFM is so often used to limit learning, not encourage it.
So yes, I see now that Section 10.2 (Page 102) "PIR Registers" of the data sheet provides the information for the code I was referring to. That's one problem down...many more to go.
Thanks again for your inputs. David.
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