Davies MSP430 Software Debounce Question

actualmente trabajando en el software rebotar botón. Usando el libro de Davies MSP430. Estoy tratando de escribir código similar en C (usando CCS) para un MSP430FR6989. El programa usa cambio de bits, y entiendo la idea de ello. Lo que no puedo entender es cómo descifrar estas # definiciones que usa Davies. No sé cómo convertir eso para el FR6989. Sigo recibiendo errores que tengo elementos indefinidos.

Al igual que defino RAW_BUTTON_PRESS1 como P1IN_bit.P1IN_1 y obtengo errores de que P1IN_bit no está definido. Tengo problemas para entender estas conversiones de asignación de pin

fragmento de davies

mi código

// Device: FR6989
// See Davies MSP430 Software Debounce starting on pg 233

#include <msp430.h>
#include <intrinsics.h>
#include <stdint.h>

union debounce{
unsigned char debounceP1IN;
struct  {
    unsigned char debounceP1IN_0 : 1;
    unsigned char debounceP1IN_1 : 1;
    unsigned char debounceP1IN_2 : 1;
    unsigned char debounceP1IN_3 : 1;
    unsigned char debounceP1IN_4 : 1;
    unsigned char debounceP1IN_5 : 1;
    unsigned char debounceP1IN_6 : 1;
    unsigned char debounceP1IN_7 : 1;
} debounceP1IN_bit;
};


#define RAW_BUTTON_PRESS1        P1IN_bit.P1IN_1
#define DEBOUNCE_BUTTON_PRESS1   debounceP1IN_bit.debounceP1IN_1
#define LED1                    P1OUT_bit.P1OUT_0

void main (void)
{
WDTCTL = WDTPW | WDTHOLD;               // stop watchdog timer
PM5CTL0 &= ~LOCKLPM5;                   // Disable the GPIO power-on default high-impedance mode

P1OUT &= ~BIT0;                     //Pre-load LED P1.0 Off
P1DIR |= BIT0;                      //Set P1.0 LED to output

P1DIR &= ~BIT1;                    //set P1.1 button to input
P1REN |= BIT1;                     //Enable Resistor Button P1.1
P1OUT |= BIT1;                     //Set as Pullup resistor Button P1.1

debounceP1IN = 0xFF;                //initialize debounce state of P1.1
TA0CCR0 = 5000;                     // TA0 interrupt triggers every 5 ms
TA0CCTL0 |= CCIE;                   //Enable TA0 interrupt
TA0CTL |= (TASSEL_2 + MC_1 + TACLR);    //SMCLK (1mhz) count to CCR0, clear timer

__enable_interrupt();

for(;;)
{
   LED1 = DEBOUNCE_BUTTON_PRESS1; //Update LED1 from debounced button
}
}

#define PRESS_THRESHOLD     0x3F
#define RELEASE_THRESHOLD   0xFC

#pragma vector = TIMER0_A0_VECTOR
__interrupt void TA0_ISR (void)
{
   static unsigned char P11ShiftReg = 0xFF; // Shift Reg for history of P1.1

P11ShiftReg >>= 1;                      // Update history in shift register
if (RAW_BUTTON_PRESS1 == 1)                         //Insert latest input from P1.1
{
    P11ShiftReg |= BIT7;                //Set MSB of Shiftreg P1.1 to 1
}

if (DEBOUNCE_BUTTON_PRESS1 == 0)                         //when debounce value is low
{
    if(P11ShiftReg >= RELEASE_THRESHOLD)    //when button is released
    {
        DEBOUNCE_BUTTON_PRESS1 = 1;                          //set new debounce state high
    }
}
else if(P11ShiftReg <= PRESS_THRESHOLD)     //when debounce value is high and button is pressed
    {
        DEBOUNCE_BUTTON_PRESS1 = 0;                          //set new debounce state low
    }
}