ADC giving weird Value!!

[Guest]

I am using an 18 seris PIC device. I am using it for reading ADC values from a sensor.
It has a 10 bit ADC.
So I implemented:
#device adc=10
right at the top of my code.

Since the default is an 8 bit ADC.

I tried reading the value of the sensor into an int16 or long variable.
When I checked the value I got 7788(hex) as my hex value. This is way… more than even the range of 1023 (dec) or 03FF(hex) that should be coming out of the ADC.
Any ideas why I could be having this problem!!

This is what I am doing:
int16 output;

SETUP_ADC_PORTS(AN0_TO_AN4 | VSS_VDD) setup_adc(ADC_CLOCK_DIV_4);

output = Read_ADC();

The value I should be getting instead of 7788(hex) should be 01FF(hex) as the voltmeter shows the output of the sensor as 2.5 V.

[PCM programmer]

Notice that the value is close to your desired result if you divide it by 64.
In other words, the 10-bit result is currently left justified in the 16-bit
word and you want it to be right justified. There is a register bit that
controls this in the PIC. See my post in the following thread:
http://www.ccsinfo.com/forum/viewtopic.php?t=29074&highlight=adfmbit

Because you're using an 18F PIC, you will have to change the register
address of the ADFM bit. (The example code is for a 16F series PIC).
Check the data sheet to find the correct register address.

[Guest]

I am using a PIC18F2520. And I implemented the following code. But it did not make any difference!

#device adc=10
#bit ADFM_BIT = 0xFC0.7
int16 output;

SETUP_ADC_PORTS(AN0_TO_AN4 | VSS_VDD)
setup_adc(ADC_CLOCK_DIV_64);

ADFM_BIT = 1;

output = Read_ADC();

The value I got for output is 7800(hex), where as I should be getting around 01FF(hex) as the voltmeter shows the output of the sensor as 2.5 V.

[PCM programmer]

Compile the code and look at the .LST file. I did that with PCH vs. 3.249
and it's there: