Here's a quickie example.

Note: I cut the trace from the pot to RA0 on my board, soldered a wire to the pot output
circuit so I can connect the output from the pot to other A/D input pins.

This leaves RA0 free for serial debugging with the PICKit2 USART tool.

Code:
@ device pic16F690, intrc_osc_noclkout, bod_off, wdt_off, mclr_off, protect_off

DEFINE OSC 4

DEFINE DEBUG_REG PORTA
DEFINE DEBUG_BIT 0      ' RA0 = TX out to PICKit2 programmer USART tool
DEFINE DEBUG_BAUD 9600
DEFINE DEBUG_MODE 0     ' 1 = inverted, 0 = true

DEFINE	ADC_BITS 10     ' Set number of bits in result
DEFINE	ADC_CLOCK 1     ' Set clock source Fosc/8 "2uS"
DEFINE	ADC_SAMPLEUS 50 ' Set sampling time in uS

Q CON 1251              ' For 10-bit A/D +Vref = 5V : 5V/1023*256=1.251=Quanta
ADval VAR WORD
Result VAR WORD

OSCCON = %01100000      ' 4MHz internal osc   
ANSEL = %00000100       ' RA2 = A/D in, rest digital
ANSELH = 0
ADCON0 = %10001001      ' Right justify, channel AN2, A/D enabled
CM1CON0 = 0
CM2CON0 = 0

PORTA = %00000001       ' serial out pin idles high
TRISA = %00000100       ' RA2 in, rest out

Main:
   ADCIN 2,ADval
   Result = ADval */ Q
   DEBUG "Raw = ",DEC ADval," Real = ",DEC Result DIG 3,".",DEC3 Result," V",13,10
   PAUSE 500
   GOTO Main

   end