Salah Mohammed <PICLIST@mitvma.mit.edu> wrote:

> I am reading the voltage on a specific pin by using the A/D(10
> bits) ,but the value in these 10 bits are not the actual value of
> the applied voltage so who can I converet it to the real value,
>
> A/D(10 bits) value                         voltage
> _______________________________________________________________
>
> 0000000000                                   0v
> .......................                      ?
> .......................                      ?
> .......................                      ?
> 1111111111                                   5v

Salah:

There are 1023 steps between zero and 5V, so each step is equal to
5V/1023, or 0.0049V.

5/1023 can be approximated by 5/1024, so to convert from A/D value to
voltage, just multiply by 5 (by left-shifting twice and adding the
original value) then divide by 1024 (by right-shifting 10 times, or
by discarding the low byte and right-shifting the rest twice).

-Andrew


=== Andrew Warren --- aiw@cypress.com
=== IPD Systems Engineering, CYSD
=== Cypress Semiconductor Corporation
===
=== Opinions expressed above do not
=== necessarily represent those of
=== Cypress Semiconductor Corporation

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads