Output ADC as binary waveform on oscilloscope

0

I´m building a project where i want to transfer an analog signal from a mikrocontroller (PIC16F1827) to an Arduino via IR-diodes. The PIC takes a analog signal (0-5 V) from a potentiometer (10k Ohm) and converts it with ADC to 8-bit digital code. After that i want to send the binary code that i get from the conversion over IR. My plan is to have the output do a squarewave signal where the a "1" = HIGH and a "0" = LOW. ex. input = 3.093V which gives the binary code "10011100" this would then be converted to a squarwave output "HIGH,LOW,LOW,HIGH,HIGH,HIGH,LOW,LOW" so that my IR diode can send it as a package.

The Arduino with an IR transmitter is connected directly to an Arduino Nano on my bread board.

The PIC code only generates a 4000 Hz PWM signal right now but thats wrong, i have not managed to get i to represent it in the wanted "bit signal". The PWM signal is correct and I can se the PWM signal good on my oscilloscope where the duty cycle span is around (0-92%) so around (0-4.6 V).

// INCLUDE
#include <stdio.h>
#include <stdlib.h>
#include <xc.h>

// CONFIG
#pragma config FOSC = HS        // Oscillator Selection bits (HS oscillator)
#pragma config WDTE = OFF       // Watchdog Timer Enable bit (WDT disabled)
#pragma config PWRTE = ON       // Power-up Timer Enable bit (PWRT enabled)
#pragma config BOREN = OFF      // Brown-out Reset Enable bit (BOR disabled)
#pragma config LVP = ON         // Low-Voltage (Single-Supply) In-Circuit Serial Programming Enable bit (RB3/PGM pin has PGM function; low-voltage programming enabled)
#pragma config CPD = OFF        // Data EEPROM Memory Code Protection bit (Data EEPROM code protection off)
#pragma config WRT = OFF        // Flash Program Memory Write Enable bits (Write protection off; all program memory may be written to by EECON control)
#pragma config CP = OFF         // Flash Program Memory Code Protection bit (Code protection off)

#define _XTAL_FREQ 4000000       //Klockoscillatorfrekvens Fosc=4 MHz
#define BAUDRATE 9600



//Datasheet PIC16F1827
//PWM on page = DS41391D-page 208


//Prototype ---------------------------------------------------------
void PWM_Initialize();
void ADC_Initialize();
unsigned int ADC_Read(unsigned char channel);
void init();
void main();

//----------------------------
void PWM_Initialize()
{
    PR2 = 254;
    CCP3CON = 0b00001100;   //CCP3 i PWM-mode
    CCPTMRS = 0b01001010;   //CCP3 use Timer2
    T2CON = 0b00100100;   //Timer2 On, Pre-scaler = 1 gives PWM = 4 kHz
    //PR2 = 0b00011001 ;
    //T2CON = 0b00000101 ;
    //CCPR1L = 0b00001100 ;
    //CCP3CON = 0b00111100 ;

}
//------------------------------
void ADC_Initialize()
{
    ADCON0 = 0x01;           //ADON 
    ADCON1 = 0b01000000;     //Left written, AD-clock = Fosc / 4, Vref VDD och VSS
    ADRESL = 0x00;
    ADRESH = 0x00; 

}
//------------------------------------------
unsigned int ADC_Read(unsigned char channel)
{
    ADCON0 = (ADCON0 & 0b10000011)|(channel<<2);         // ADC-channel
    __delay_us(5);         //Delay 5us. Macro i HITECH C.
    ADCON0bits.GO=1;       //AD-converter start
    while(ADCON0bits.GO);  //Wait for AD-convertion to finish
    //return ((ADRESH<<8) +ADRESL); //Returns 10 bit Result
    return ADRESH;         //Return 8 MSB of AD-convertion 
}
//----------------------------------------------
void init()
{
    OSCCON = 0b01101000;    //Intern clock 4 MHz
    OSCTUNE = 0x00;         // TUN 0;
    BORCON = 0x00;          // SBOREN disabled;
    ANSELA = 0b00000001;    //PortA bit 0 (RA0) analog, all other bit digital
    ANSELB = 0b00000000;    //PORTB alla bits digital
    TRISA =  0b00100001;    //PORTA bit 0 (RA0) and 5 (RA5) input, rest output
    TRISB =  0x00000000;    //PORTB all as output
}
//Main-program ----------------------------------------------------------------
void main()
{
    int adc_value;
    init();               // Init PORTS
    ADC_Initialize();     // Initializes ADC Module
    PWM_Initialize();     // This sets the PWM frequency of PWM1
    do
    {
        adc_value = ADC_Read(0);        //Reading Analog Channel 0 from RA0
        PORTB = adc_value;              // Indicate bit numbers with 8 LED´s on PORT (RB0-RB7) for tetsing 
        __delay_ms(50); 
        CCPR3L = adc_value;             // ADC to PWM signal converter
        __delay_ms(50); 

    }while(1); //Infinite Loop

How do i get this conversion? Like this:

enter image description here

I have no knowledge i how to set a squarewave HIGH for x us "to represent a 1 in the squarewave output" and set the squarewave LOW for y us "to represent a 0 in the squarewave output"

so for exempel how do i write a code that for Ex


if ADC_read = "1"
 set squarewave HIGH for 600 us;

if ADC_read"0"
  set squarewave LOW for 1000 us;

enter image description here

Would appreciate any help, Thanks!

c
arduino
pic
mplab
asked on Stack Overflow Mar 28, 2019 by Filip Kaiser • edited Mar 28, 2019 by Filip Kaiser

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