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Date: Fri, 01 Aug 2014 21:47:20 +0100
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Subject: Re: Creating a 2s compliment hex string for negitive numbers
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On 2014-08-01 21:35, bSneddon wrote:
> I need to calculate an error correction code for an old protocol.
>
> I calculate the integer 4617 and want to code the 2s compliment in ASCII
> hex EDF7.  When issue the following.
>>>> hex(-4617)
> '-0x1209'
>
> Does anyone know a clean way to get to the desired results?   My ECC will always
> be 16 bit (4 nibble) hex number.
>
Use a bitwise AND:

 >>> hex(-4617 & 0xFFFF)
'0xedf7'