adc.h- (658 Bytes) Downloaded 621 times
* Header file for the ADC unit - designed for PIC16F876/7
* BE CAREFUL WITH ADCON1 - IT HAS TO BE MANUALLY ADJUSTED FOR YOUR HARDWARE
* IN THE InitialiseADC ROUTINE.
*/
/*
sample C code
InitialiseADC(--Channel--);
blah = ReadADC(--Channel--);
*/
#include <pic.h> // Pic CPU header file
//#include "control.h"
#define INPUT 1
/*---------------------------------------------------------------
Initialising the ADC channels
---------------------------------------------------------------*/
void InitialiseADC (unsigned char ADC_Channel) {
if (ADC_Channel == 0) TRISA0 = INPUT;
else if (ADC_Channel == 1) TRISA1 = INPUT;
else if (ADC_Channel == 2) TRISA2 = INPUT;
else if (ADC_Channel == 3) TRISA3 = INPUT;
/* ------
Specify all to be analogue inputs, refered to VDD.
Please refer to Page 118 from PIC manual for other configurations.
------ */
/* Analogue-RA0/RA1/RA3 Digital-RA2/RA5 */
ADCON1 = 0b10000100;
}
/*---------------------------------------------------------------
Reads the ADC level input on a specified ADC channel.
Takes in an 10-bit ADC channel number.
Returns an 10 bit number that signifies this level.
Approximate sampling time = 76.8us
---------------------------------------------------------------*/
unsigned int ReadADC(unsigned char ADC_Channel){
volatile unsigned int ADC_VALUE;
/* Selecting ADC channel */
ADCON0 = (ADC_Channel << 3) + 1; /* Enable ADC, Fosc/2 */
ADIE = 0; /* Masking the interrupt */
ADIF = 0; /* Resetting the ADC interupt bit */
ADRESL = 0; /* Resetting the ADRES value register */
ADRESH = 0;
ADGO = 1; /* Staring the ADC process */
while(!ADIF) continue; /* Wait for conversion complete */
ADC_VALUE = ADRESL; /* Getting HSB of CCP1 */
ADC_VALUE += (ADRESH << 8); /* Getting LSB of CCP1 */
return (ADC_VALUE); /* Return the value of the ADC process */
}