PIC16F72 microcontorller ADC interfacing

[kushal nandanwar]

I have uploaded my PIC16F72 code for interfacing 4 Analog channel, but ADC not reading any data from output channel, I have used 1.8MHz crystal, required 1KHz PWM with varying duty cycle, pls help me.

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Code C - [expand]
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#include <htc.h>
#include<pic.h>
#include <stdio.h>
 
void DELAY( void );
 
#define DATA ADRES
#define _XTAL_FREQ 1800000
 
 
unsigned int   Power,Power1, battery_Power;
unsigned int  Voltage, Current, battery_Voltage, battery_Current, 
                  DUTY =0x00;
 
#pragma config WDTEN = OFF
#pragma config OSC = XT
   
 
 
 
void main(void)
{
    CCP1CON = 0x00;
    PR2 = 0x1D;                                            /* Set Time Period Value */
 
    TRISC=0x00;                                               /* Set RC as an output pin */ 
    PORTC=0x00;
       
    TRISA =1;                                             /* Set RA as an INPUT pin */
    PORTA =1;
                                                          
    T2CON = 0x03;                                          /* 16 Prescalers Timer 2 */
    CCP1CON = 0x0C;                                        /* PWM Mode */
    CCPR1L = DUTY;                            
    
    TMR2ON = 1;                                            /* Timer 2 ON */  
 
while(1)                                                   /* infinit loop*/
{ 
                                                             
 
 /* analog channel setting for first sample*/                     
 
 /* analog channel setting for voltage*/
 
 /* AN0 analog input for voltage*/
 
 
ADCON0 = 0b01000001;                                              /* strat ADC */
ADCON1 = 0x00;                                               /*define port A as an analog port*/ 
DELAY();
GODONE=1;                                                    /*begin  conversion */
while(GODONE == 0);                                          /* Wait for the conversion to end*/
Voltage = DATA;                                              /* Save voltage in ADRESH as Voltage_Step_Number*/
 
       /* analog channel setting for current*/
 
       /* AN1 analog input for current*/
 
ADCON0 = 0b01010000;                                               /* strat ADC */
ADCON1 = 0x00;                                                /*define port A as an analog port*/ 
ADON=1;
GODONE=1;                                                     /*begin  conversion */
while(GODONE == 0);                                           /* Wait for the conversion to end*/
Current = DATA;                                               /* Save voltage in ADRESH as Voltage_Step_Number*/
 
if((Current >0) && (Voltage > 0))
{
RC1=1;                                                        /*machine ON/OFF pin*/
RC3=1;                                                       /* program running indicator LED */
RC0=RC2;                                                     /* BATTERY CHARGER INDICATOR */
 
Power=Voltage*Current;                                        /* POWER CALCULATION */
 
 
      /* analog channel setting for second sample*/
 
      /* analog channel setting for voltage*/
 
      /* AN0 analog input for voltage*/
 
ADCON0 = 0b01000000;                                                /* strat ADC */
ADCON1 = 0x00;                                                 /*define port A as an analog port*/ 
ADON=1;
GODONE=1;                                                      /*begin  conversion */
while(GODONE == 0);                                            /* Wait for the conversion to end*/
Voltage = DATA;                                                /* Save voltage in ADRESH as Voltage_Step_Number*/
 
    /* analog channel setting for current*/
 
    /* AN1 analog input for voltage*/
 
ADCON0 = 0b01010000;                                                 /* strat ADC */
ADCON1 = 0x00;                                                  /*define port A as an analog port*/ 
ADON=1;
GODONE=1;                                                       /*begin  conversion */
while(GODONE == 0);                                             /* Wait for the conversion to end*/
Current = DATA;                                                 /* Save voltage in ADRESH as Voltage_Step_Number*/
 
Power1=Voltage*Current;                                         /* N+1 POWER CALCULATION */
 
 
    /* analog channel setting for batter voltage*/
 
    /* AN2 analog input for voltage*/
 
ADCON0 = 0b01001000;                                                  /* strat ADC */
ADCON1 = 0x00;                                                   /*define port A as an analog port*/ 
ADON=1;
GODONE=1;                                                        /*begin conversion */
while(GODONE == 0);                                              /* Wait for the conversion to end*/
battery_Voltage = DATA;                                          /* Save voltage in ADRESH as Voltage_Step_Number*/
 
    /* analog channel setting for batter  current*/
 
    /* AN3 analog input for voltage*/
 
ADCON0 = 0b01011001;                                                  /* strat ADC */
ADCON1 = 0x00;                                                   /*define port A as an analog port*/ 
ADON=1;
GODONE=1;                                                        /*begin conversion */
while(GODONE == 0);                                              /* Wait for the conversion to end*/
battery_Current = DATA;                                          /* Save voltage in ADRESH as Voltage_Step_Number*/
 
 
battery_Power=battery_Voltage*battery_Current;                   /* POWER CALCULATION FOR REFERANCE */
 
                                                                 /*comparision loop for changing duty cycle*/
                                                                                                                                                                                                   /* Compare Voltage and power to previous and increment/decrement DUTY cycle*/
 
if(Power1 >Power )
{    
 DUTY++;
 DELAY();
}
 else if (Power< Power1)
{
 DUTY--;
 DELAY();
} 
 
}
else
{
RC1=0;                                                             /*machine ON/OFF pin*/
DELAY();
}    
}                                                                                                      
}
 
 
void DELAY ()                                                     /*delay program*/
{ 
unsigned char cnt = 4000;                                      // Delay Cycle to achieve  delay 
while(--cnt != 0);                                              // Delay Timing is approximately 3 usec per loop 
                                                              
}

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I have uploaded my PIC16F72 code for interfacing 4 Analog channel, but ADC not reading any data from output channel, I have used 1.8MHz crystal, required 1KHz PWM with varying duty cycle, pls help me.

 

[Jinzpaul4u]

Hi there,

Try this example and revert back me

https://ww1.microchip.com/downloads/en/DeviceDoc/04_A2D.zip

Best regards,

 

[kushal nandanwar]

Hi there,

Try this example and revert back me

https://ww1.microchip.com/downloads/en/DeviceDoc/04_A2D.zip

Best regards,

thanks sir,

but still hardware is not working

 

[Jinzpaul4u]

Hello there,

What happended for your hardware?

If you don't mind connect one of the adc channel to power supply (0V-2.5V) and try to read it. Make sure your circuit ground is common.

Best regards,

 

[kushal nandanwar]

Hello sir ,

thanks too much ,my ADC start working ,but still there is problem, PWM is not generating at output ,pls send me program for PWM, i want PWM with frequency 1KHz ,with varying duty cycle. my crystal frequency is 1.8 MHz.

thanks