ADC Congfiguration (vref) on 12F675

[rashworth]

I am trying to use Vref on the 12F675. I only require A0, as an analogue input, but I need to use A1 as the reference. How is this accomplished using the 12F675?

[Felix Althaus]

Hello

In the PIC12CE674 header file I found defined this:
AN0_ANALOG_AN1_REF
I don't know exactly the 12F675 but I bet you can use this setup constant with it.

May you want to have a look into the 12F675.H header file.

mfg
Felix

[arif]

try this
it is working.

#include <12f675.h>
#device adc=10
#use delay(clock=4000000)
#fuses intrc_io,noWDT,NOPROTECT,NOMCLR,NOBROWNOUT


#byte ADCON0 =0x1f
#byte ADRESL =0x9E
#bit VREFF =ADCON0.6


main()
{
setup_adc_ports(AN0_ANALOG);
setup_adc(internal);
VREFF=1;

while(true)
{
xxxxx;
}
}

[rashworth]

Thanks Arif,

All is now working.

It appears the header file is missing some useful info for setting up the ADC reference voltage.

Rob