Battery checker

[lerameur]

I got it working but have no clue why .
If i do what is on the pic :
http://www3.sympatico.ca/lerameur/
then it works.
In this manner the output voltage also moved at the same time as the reference voltage no ?

[lerameur]

Anybody ??

[Acetronics2]

Hi,

I think ( ! ) a look to the '88 Datasheet ( ADC config ) could help you a bit ...

Alain

PS: common diodes as voltage refs ... that's a bit rock and roll ...

[lerameur]

I just changes the circuit a bit. I have new ideas this morning. night was good.
I am getting 1.06v steady on the diode as reference. My voltage divider shows me 0.7, but I am getting zero as output now.
Is it the hardware or the programming ?
I posted a new pic.
http://www3.sympatico.ca/lerameur/
also changed this line:
ADCON1 = %10010010


ken

[brianwu]

but I am getting zero as output now.
Is it the hardware or the programming ?
I posted a new pic.
http://www3.sympatico.ca/lerameur/

ken

Picture show you have both input connected to same place (ref. diode), resistor divider left unconnected.

[lerameur]

I got it going somehow. I dont even know what I was doing wrong...
maybe I am still sleeping
k

[lerameur]

Ok I think I know where lies the confusion.
Ihave two batteries I want to check.I can check the battery that powers the microcontroller with voltage reference. I am trying to check the second battery . There is no common ground and I dont want one because of the isolation I want to have. Therefore I think when I do an A/D, is reads as a floating value.
How do I go around this ?