RE: Bit Operations

["Fisher, Don" <dfisher@xxxxxxxxxxxxx>]

Joe, thank you very much for that thorough explanation.  I believe I mostly
understand this now.  

Thanks also for saving me the research into which hex values correspond to
the bit values to be tested.

And thanks to everyone else who provided insight into this issue for me.
It's most appreciated.

Donald R. Fisher, III
Project Manager
Roomstore Furniture Company
(804) 784-7600 extension 2124
DFisher@xxxxxxxxxxxxx

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So, let's look at a couple more examples:

B'0001 0000' AND B'0001 0000' = B'0001 0000'
B'0001 1111' AND B'0001 0000' = B'0001 0000'
B'0101 0101' AND B'0001 0000' = B'0001 0000'
B'1111 1111' AND B'0001 0000' = B'0001 0000'

Get the idea?  Basically, the AND strips out anything except where you have
bits on in the mask.  So, in this particular case, as long as bit
one is on, the result will be B'0001 0000'.  Similarly, anything with bit
one off will end up as B'0000 0000':

B'0000 0000' AND B'0001 0000' = B'0000 0000'
B'0000 1111' AND B'0001 0000' = B'0000 0000'
B'0000 0101' AND B'0001 0000' = B'0000 0000'
B'1110 1111' AND B'0001 0000' = B'0000 0000'

Because there is only one bit on in your mask, there are only two possible
results: if bit three is on, the result is B'0001 0000', if bit
three is off, the result is B'0000 0000'.
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