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<== Date ==> <== Thread ==>

Subject: Re: Small patch for asynMask bitmask values
From: Angus Gratton <[email protected]>
To: Eric Norum <[email protected]>
Cc: tech-talk <[email protected]>
Date: Fri, 20 Aug 2010 13:38:32 +1000
Hi Eric,

On Thu, 2010-08-19 at 19:13 -0700, Eric Norum wrote:
> The 1<<N form seems reasonable, but I'm not 100% that the bitXX names are a good idea.   My concern stems from the fact that some architectures number bits from the right (which is what I presume this patch does) while others number them from the left.  Thus 'bit14' is somewhat ambiguous.

That seems fair enough. I hadn't considered different bit numbering
conventions. FWIW, the documentation section describes 'bitX' as
equivalent to '1<<X', but I can still see your point.

I have no objection to swapping the string "bit" for "1<<" in the patch.

The reason why I didn't go with '1<<' up front is that this implies
there may be a more complete set of expressions available to the user.
Which could also be nice to have, but I think would require a more
complex parser for @asynMask fields. Unless there's one elsewhere in
EPICS (CALC?) that could readily be plugged in?


- Angus



Replies:
Re: Small patch for asynMask bitmask values Eric Norum
References:
Small patch for asynMask bitmask values Angus Gratton
Re: Small patch for asynMask bitmask values Eric Norum

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