analog 2 digital converter...

hi all.

i'm now reading in some voltages..

but the thing i find is that the maximum value i find = 1019/1020

and not the 1023..

i have put 2 resistors in series and the in the middle of them i puted a wire to the pic..

and the last res is a resistor you can adjust..whit a button...

it also can draw to 0 ohm...


i don't untherstand wy i read 1020 in stead of 1023 any one suggestions..

TKS

my vref = 5,07 volt says my multimeter..

Try posting the circuit, the obvious answer is that your input isn't reaching the reference voltage.

1. Make sure you have the ADC conversion clock divider set correctly for your clock freq.
2. Make sure you have waited the minimum time after the ADC has been enabled and you have selected the desired channel before setting the GO bit.

VDD

even when i put it strait to VDD it says that...

i compare also to VDD

so it should says 1023 then...

TKS