I was trying to decide which reference voltage to use for a project
and had one of those 'moments'. I need a reality check please

PICs are said in their manuals to have 1024 steps, but 0 to 0x3ff
is 1023 steps. There are 1024 digital output values, including 0

So, if you have a 4.096V Vref, that actually equates to, according
to me, 4.0039mV per step, not a tidy 4.0000mV. And with 5.120V
Vref it's 5.0049mV per step, not 5.0000mV

Have I overlooked that for all these years ? I'm not sure it will have
too great an effect on most A/D useage, but wonder if (assuming I'm
correct) anyone compensates at all for it, eg with an adjusted Vref 

Or am I still in the 'moment' ?

TIA

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