LAB6

/*
 * File:   main.c
 * Author: Jon Mills
 * Date: 2019-11-08
 * Version: 1
 * Title: Lab 6
 * Description: Takes in an input analog value and turns on a corresponding LED
 *
 *
 *
 */


// PIC18F45K22 Configuration Bit Settings

// 'C' source line config statements

// CONFIG1H
#pragma config FOSC = INTIO67   // Oscillator Selection bits (Internal oscillator block)
#pragma config PLLCFG = OFF     // 4X PLL Enable (Oscillator used directly)
#pragma config PRICLKEN = ON    // Primary clock enable bit (Primary clock is always enabled)
#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor Enable bit (Fail-Safe Clock Monitor disabled)
#pragma config IESO = OFF       // Internal/External Oscillator Switchover bit (Oscillator Switchover mode disabled)

// CONFIG2L
#pragma config PWRTEN = OFF     // Power-up Timer Enable bit (Power up timer disabled)
#pragma config BOREN = OFF      // Brown-out Reset Enable bits (Brown-out Reset disabled in hardware and software)
#pragma config BORV = 190       // Brown Out Reset Voltage bits (VBOR set to 1.90 V nominal)

// CONFIG2H
#pragma config WDTEN = OFF      // Watchdog Timer Enable bits (Watch dog timer is always disabled. SWDTEN has no effect.)
#pragma config WDTPS = 32768    // Watchdog Timer Postscale Select bits (1:32768)

// CONFIG3H
#pragma config CCP2MX = PORTC1  // CCP2 MUX bit (CCP2 input/output is multiplexed with RC1)
#pragma config PBADEN = ON      // PORTB A/D Enable bit (PORTB<5:0> pins are configured as analog input channels on Reset)
#pragma config CCP3MX = PORTB5  // P3A/CCP3 Mux bit (P3A/CCP3 input/output is multiplexed with RB5)
#pragma config HFOFST = ON      // HFINTOSC Fast Start-up (HFINTOSC output and ready status are not delayed by the oscillator stable status)
#pragma config T3CMX = PORTC0   // Timer3 Clock input mux bit (T3CKI is on RC0)
#pragma config P2BMX = PORTD2   // ECCP2 B output mux bit (P2B is on RD2)
#pragma config MCLRE = EXTMCLR  // MCLR Pin Enable bit (MCLR pin enabled, RE3 input pin disabled)

// CONFIG4L
#pragma config STVREN = ON      // Stack Full/Underflow Reset Enable bit (Stack full/underflow will cause Reset)
#pragma config LVP = OFF        // Single-Supply ICSP Enable bit (Single-Supply ICSP disabled)
#pragma config XINST = OFF      // Extended Instruction Set Enable bit (Instruction set extension and Indexed Addressing mode disabled (Legacy mode))

// CONFIG5L
#pragma config CP0 = OFF        // Code Protection Block 0 (Block 0 (000800-001FFFh) not code-protected)
#pragma config CP1 = OFF        // Code Protection Block 1 (Block 1 (002000-003FFFh) not code-protected)
#pragma config CP2 = OFF        // Code Protection Block 2 (Block 2 (004000-005FFFh) not code-protected)
#pragma config CP3 = OFF        // Code Protection Block 3 (Block 3 (006000-007FFFh) not code-protected)

// CONFIG5H
#pragma config CPB = OFF        // Boot Block Code Protection bit (Boot block (000000-0007FFh) not code-protected)
#pragma config CPD = OFF        // Data EEPROM Code Protection bit (Data EEPROM not code-protected)

// CONFIG6L
#pragma config WRT0 = OFF       // Write Protection Block 0 (Block 0 (000800-001FFFh) not write-protected)
#pragma config WRT1 = OFF       // Write Protection Block 1 (Block 1 (002000-003FFFh) not write-protected)
#pragma config WRT2 = OFF       // Write Protection Block 2 (Block 2 (004000-005FFFh) not write-protected)
#pragma config WRT3 = OFF       // Write Protection Block 3 (Block 3 (006000-007FFFh) not write-protected)

// CONFIG6H
#pragma config WRTC = OFF       // Configuration Register Write Protection bit (Configuration registers (300000-3000FFh) not write-protected)
#pragma config WRTB = OFF       // Boot Block Write Protection bit (Boot Block (000000-0007FFh) not write-protected)
#pragma config WRTD = OFF       // Data EEPROM Write Protection bit (Data EEPROM not write-protected)

// CONFIG7L
#pragma config EBTR0 = OFF      // Table Read Protection Block 0 (Block 0 (000800-001FFFh) not protected from table reads executed in other blocks)
#pragma config EBTR1 = OFF      // Table Read Protection Block 1 (Block 1 (002000-003FFFh) not protected from table reads executed in other blocks)
#pragma config EBTR2 = OFF      // Table Read Protection Block 2 (Block 2 (004000-005FFFh) not protected from table reads executed in other blocks)
#pragma config EBTR3 = OFF      // Table Read Protection Block 3 (Block 3 (006000-007FFFh) not protected from table reads executed in other blocks)

// CONFIG7H
#pragma config EBTRB = OFF      // Boot Block Table Read Protection bit (Boot Block (000000-0007FFh) not protected from table reads executed in other blocks)

// #pragma config statements should precede project file includes.
// Use project enums instead of #define for ON and OFF.

#include <xc.h>
#define _XTAL_FREQ 8000000

void main(void)
{
    int conversion = 51; //explained further down
    TRISA = 1;
    TRISC = 0; //set outputs
    LATC = 0;
    ANSELA = 1; //set all ports at port A to be analog input bits. we're only going to use 1, but im lazy
    ADCON0 = 0x1; //select AN0, turn on the ADC, but don't start acqusition!
    ADCON1 = 0x0; //the bits to configure the voltage reference at VSS and VDD are 00 and 00.
    ADCON2 = 0b00101000;

    while (1)
    {

        ADCON0bits.GODONE = 1; //start the acqusition
        while (ADCON0bits.GODONE == 1)
        {
            //... empty, just waiting for the conversion to be done
        }
        //we will convert our result to integer so that it can be sent to the correct LED
        //+1 to the overall byte is  0.004882.
        //+1 to the HIGH result is  0.004882*4 or 0.0195.
        //11111111 is 5-4.98V, and 00000000 is 0-0.02 V approx.
        int ad_result = ADRESH;
        //we should convert the result, since it isn't quite what we're asking for
        //the divisions are approx. 51.
        //therefore, we can divide the result by 51 to get a value between 0 and 5 to send
        //we also
        int converted = ((ad_result - 2) / 51);
        //next, decode the value by setting the corresponding bit...
        int decoded = 0;
        decoded |= 1UL << converted; //i found this code on stack overflow.
        //it uses the bit shift operator to to put a 1 at the correct bit.
        //1UL is an unsigned long that has the form of 31 zeroes followed by a 1.
        //this single bit is then shifted left by the amount that was found by the conversion.
        //the bitwise OR operator guarantees that a 1 is written to this bit.
        LATC = 0;
        LATC = decoded; //send it to the corresponding bit
    }
}