MSP430I2020: UART RX interrupt reading wrong data?

Hello! I use a MSP432 to send UART data over RS485 to a MSP430. The problem is that the MSP430 reads only 0xFF and 0xFE and receives only one out of each two bytes.

This is my schematic:

This is my code:

int NUM_OF_TX_BYTES = 0;

char uart_rxBuffer[UART_BUFFER_SIZE];
volatile uint32_t xferIndex = 0;
char uart_txBuffer[UART_BUFFER_SIZE];

volatile bool uartRxFlag = false;

void UART_init(void)
{
    // Configuration for 9600 UART with SMCLK at 16384000
    // software-dl.ti.com/.../index.html
    EUSCI_A_UART_initParam uartConfig = {
        EUSCI_A_UART_CLOCKSOURCE_SMCLK,                 // SMCLK Clock Source
        106,                                            // BRDIV = 8
        10,                                             // UCxBRF = 14
        206,                                            // UCxBRS = 34
        EUSCI_A_UART_NO_PARITY,                         // No Parity
        EUSCI_A_UART_LSB_FIRST,                         // LSB First
        EUSCI_A_UART_ONE_STOP_BIT,                      // One stop bit
        EUSCI_A_UART_MODE,                              // UART mode
        EUSCI_A_UART_OVERSAMPLING_BAUDRATE_GENERATION  // Oversampling Baudrate
    };

    // Configure pins
    GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P1, GPIO_PIN2 | GPIO_PIN3, GPIO_PRIMARY_MODULE_FUNCTION);

    // Configure and enable the UART peripheral
    EUSCI_A_UART_init(EUSCI_A0_BASE, &uartConfig);
    EUSCI_A_UART_enable(EUSCI_A0_BASE);
    EUSCI_A_UART_enableInterrupt(EUSCI_A0_BASE, EUSCI_A_UART_RECEIVE_INTERRUPT);
}

#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=USCI_A0_VECTOR
__interrupt
#elif defined(__GNUC__)
__attribute__((interrupt(USCI_A0_VECTOR)))
#endif
void USCI_A0_ISR(void) {
    switch(__even_in_range(UCA0IV, USCI_UART_UCTXCPTIFG)) {
        case USCI_NONE: break;
        case USCI_UART_UCRXIFG:

            uart_rxBuffer[xferIndex++] = EUSCI_A_UART_receiveData(EUSCI_A0_BASE);
            if (uart_rxBuffer[xferIndex - 1] == '\0')
            {
                xferIndex = 0; // Reset index if at end of array
                uartRxFlag = true;
                __bic_SR_register_on_exit(LPM0_bits); // Wake up
            }

            break;
        case USCI_UART_UCTXIFG: break;
        case USCI_UART_UCSTTIFG: break;
        case USCI_UART_UCTXCPTIFG: break;
        default: break;
    }
}

I've used a logic analyzer to verify and I confirm that the data correctly reaches the MSP430, on pin UART_A0_RXD (e.g. message: "0;1\0"). I put a breakpoint inside the RX ISR and it hits every two bytes, and the RX buffer contains only 0xFF or 0xFE, alternatively.

What is wrong? Is there a problem with my code or with the MCU?