Il 16/04/2012 00:42, Jonas Maebe ha scritto:
On 16 Apr 2012, at 00:38, Giuliano Colla wrote:
I'm dealing with a large number of data coming from an external device.
They are big-endian 16 bits signed numbers, which must be converted to integer
and to real to perform calculations.
Besides the obvious solutions of treating them as isolated bytes, multipying by
256 the highest, adding the lower, and oring wit $FFFF0000, or whatever
sizeof(Integer) suggests if the result is bigger than 32767, is there a more
efficient and elegant way to achieve the result?
Call BEtoN() on them (Big Endian to Native byte order). Note that this routine is
overloaded for all integer sizes> 1, and that FPC extends the size of any
number< 32/64 bits (depending on the architecture) to 32/64 bits when performing
almost any operation on it. It's therefore probably the safest to call it as
BEtoN(smallint(value)) to ensure that the correct overload is selected.
I was sure that hidden somewhere there was a better way!
Thanks a lot
Giuliano
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