> But if you look at the block diagram for pins RB6 and RB7,
> signal T1OSCEN is used to disable RBIF being set from
> those inputs when it's active.

Ah, quite right. I followed T1OSCEN through the gates but
didn't spot that it's inverted at the ANDs that are part of the
RBIF lines. In which case, it should work. And like so many
things when you're not sure, it's just as quick to wire it up
and try it

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