CCS/MSP430FR2355: AC Signal ADC help

Part Number: MSP430FR2355

Tool/software: Code Composer Studio

Hello everyone,

I am currently using an MSP430FR2355 and am trying to take in an ECG signal using ADC Channel 1. The minimum voltage of the signal is roughly 200mV and the maximum voltage is 2.4V. I would like to take the adc values in continuously off this channel so that I can output them to an OLED display. However, when I run the code provided below, every value in the array is equal to 1. I am sure I am doing something wrong, however I am unable to figure it out. Any help would be greatly appreciated. Thanks in advance!

#include <msp430.h>
#include <stdio.h>
#include <math.h>
#include <stdint.h>
#include <stdlib.h>

#include "msp430fr2355.h"

void adc_init(void);

void adc_init(void){

    P1SEL0 |= BIT1;
    P1SEL1 |= BIT1;

    ADCCTL0 &= (~ADCENC);

    ADCCTL0 |= ADCSHT_0 + ADCON; // need to turn on ADCENC at end
    ADCCTL1 |= ADCSSEL_0 + ADCCONSEQ_2;
    ADCCTL2 |= ADCPDIV_2 + ADCRES_2 + ADCSR;

    ADCMCTL0 |= ADCSREF_0 + ADCINCH_1;

    ADCCTL0 |= ADCENC;

}

int main(void)
{
	WDTCTL = WDTPW | WDTHOLD;	// stop watchdog timer
	PM5CTL0 &= ~LOCKLPM5;
	
	uint16_t ADC_temp[100] = {};
	uint8_t i;

	adc_init();

    ADCCTL0 |= ADCENC + ADCSC;
    for(i = 0; i < 100; i++){
        while(!ADCBUSY);
        ADC_temp[i] = ADCMEM0;
    }

    while(1);
	return 0;
}