/* ADC - Potentiometer to LEDs
 *
 * In this example, conversion result memory register 5 is used.
 * Analog input channel 6 using pin P4.7 is configure for result
 * memory register 5. P4.7 is connected to the potentiometer of the
 * EduPad board. Conversion is started by software trigger.
 * The bits 10-8 of the 12 bit conversion result are displayed on
 * the LED3 - LED0.
 *
 * Built and tested with MSP432P401R Rev. C, Keil MDK-ARM v5.24a and MSP432P4xx_DFP v3.1.0
 */

#include "msp.h"

void display(int data);

int main(void) {
    int result;

    P2->DIR |= 0x30;     /* P2.5, P2.4 set as output for LEDs */
    P3->DIR |= 0x0C;     /* P3.3, P3.2 set as output for LEDs */

    ADC14->CTL0 =  0x00000010;      /* power on and disabled during configuration */
    ADC14->CTL0 |= 0x04080300;      /* S/H pulse mode, sysclk, 32 sample clocks, software trigger */
    ADC14->CTL1 =  0x00000020;      /* 12-bit resolution */
    ADC14->MCTL[5] = 6;             /* A6 input, single-ended, Vref=AVCC */
    P4->SEL1 |= 0x80;               /* Configure P4.7 for A6 */
    P4->SEL0 |= 0x80;
    ADC14->CTL1 |= 0x00050000;      /* convert for mem reg 5 */
    ADC14->CTL0 |= 2;               /* enable ADC after configuration*/

    while (1) {
        ADC14->CTL0 |= 1;           /* start a conversion */
        while (!ADC14->IFGR0);      /* wait till conversion complete */
        result = ADC14->MEM[5];     /* read conversion result */

        /* display bits 10-8 on the LEDs */
		display(result >> 8);
    }
}

void display(int data) {		
    if (data & 8)              /* bit 3 -> LED3 */
        P2->OUT |= 0x10;
    else
        P2->OUT &= ~0x10;
    
    if (data & 4)              /* bit 2 -> LED2 */
        P2->OUT |= 0x20;
    else
        P2->OUT &= ~0x20;
    
    if (data & 2)              /* bit 1 -> LED1 */
        P3->OUT |= 8;
    else
        P3->OUT &= ~8;
    
    if (data & 1)              /* bit 0 -> LED0 */
        P3->OUT |= 4;
    else
        P3->OUT &= ~4;        
}