Code Problem?

[Archilochus]

Hi Scott,
I'm not too familiar with the '675, but don't you need to set your ANSEL register so that GP.1 is an analog input? It looks like only GP.0 is set as analog in.

Arch

[scottl]

Arch,

You are correct! I have changed this to ANSEL = 51 or ANSEL = %00110011. I have changed this but have the same problem! It only reads 32 over SEROUT2 no change.

If I rem out the ADCIN1 I get the correct value via ADCIN0 checked by multimeter. It only happens when I add ADCIN1. Does it look like the ADCON0 register?

Any other suggestions?

Thanks,

Scott

[Archilochus]

I've not used ADCIN much, but here's some other things to check:

I don't see anywhere in your code that sets the pins as inputs - you might try setting up the TRISIO register as needed.

In the PBP manual it shows an example like this:
"ADCIN 0, B0 ; Read channel 0 to B0"

The 'channel' is selected with a number rather than port pin name - don't know if that makes any difference or not.

Arch

[modifyit]

Here is another way of aproaching the A/D based on some code Melanie posted a long time ago, this uses direct access to the pics registers instead of using PBP's routines:

 Analog_In:
     ANSEL=%00110001
    ADCON0=%10000001;
        ' Enable ADC Module on pin AN0
    PauseUS 50;
        ' 50uS Pause to allow sampling Capacitor to charge
    ADCON0.1=1
    ' Start Conversion
    While ADCON0.1=1:Wend
    ' Wait for conversion to complete
    AnalogIn.Highbyte=ADRESH
    AnalogIn.Lowbyte=ADRESL
    ' Read 16-bit Result
RETURN

By changing ADCON0 to different values you should be able to read analog in on all the other analog pins