AD7190 default register not read

Hello Everyone,

  I am trying to communicate between AD7190 and MSP432P401M controller through SPI communication. My issue is I can't read default register value from AD7190.
I have attached circuit diagram and code for your reference.

The connections are as follows:-

Pin no 13,14 -left open

PIn no. 17 to GND

pin no 22 (SYNC') tied to 3.3V 

pin no. 5,6,7,8 left open

#include "msp.h"
#include "common.h"
#include "AD7730.h"

//**************SPI Initialization*******************//
void SPI_INT()
{
   P1->SEL0 |= BIT4 | BIT5 | BIT6 | BIT7;          // set 4-SPI pin as second function

   EUSCI_B0->CTLW0 |= EUSCI_B_CTLW0_SWRST;          // Put eUSCI state machine in reset
   EUSCI_B0->CTLW0 = EUSCI_B_CTLW0_SWRST |          // Remain eUSCI state machine in reset
                     EUSCI_B_CTLW0_MST |            // Set as SPI master
                     EUSCI_B_CTLW0_SYNC |           // Set as synchronous mode
                     EUSCI_B_CTLW0_MSB|             // MSB first
                     EUSCI_B_CTLW0_MODE_2 |         // 4-pin mode with slave enable when STE low
                     EUSCI_B_CTLW0_STEM |           // STE mode select
                     EUSCI_B_CTLW0_SSEL__SMCLK;     // SMCLK
   // Clock polarity initially low
   //data out on first rising edge
   //data out on first falling edge
   //this setting are according to AD7730 CLK_POL tie to ground or Zero
   EUSCI_B0->BRW = 0x01;                            // /2,fBitCl0ock = fBRCLK/(UCBRx+1).
   EUSCI_B0->CTLW0 &= ~EUSCI_B_CTLW0_SWRST;         // Initialize USCI state machine

}

//*************SPI transmit*****************
void spi_tx(uint8_t txdata)
{
   while(!(EUSCI_B0->IFG & EUSCI_B_IFG_TXIFG));
   EUSCI_B0->TXBUF = txdata ;
}

//***********Function to write internal register
void WriteRegister(uint8_t W_address, int N_OF_Byte, int data)
{
    /* local variable declaration */
      int var32bit=data;
      uint8_t var8bit1,var8bit2,var8bit3,var8bit4;

      var8bit1 = var32bit;         // Lower Order byte
      var8bit2 = var32bit >> 8;
      var8bit3 = var32bit >> 16;
      var8bit4 = var32bit >> 24;   // Higher Order Byte

      spi_tx(W_address);
      __delay_cycles (200);
      if(N_OF_Byte==1)
       {
          spi_tx(var8bit1);
          __delay_cycles (200);
       }
      if(N_OF_Byte==2)
       {
          spi_tx(var8bit2);
          __delay_cycles (200);
          spi_tx(var8bit1);
          __delay_cycles (200);
       }

      if(N_OF_Byte==3)
       {
          spi_tx(var8bit3);
          __delay_cycles (200);
          spi_tx(var8bit2);
          __delay_cycles (200);
          spi_tx(var8bit1);
          __delay_cycles (200);
        }

      if(N_OF_Byte==4)
      {
          spi_tx(var8bit4);
          __delay_cycles (200);
          spi_tx(var8bit3);
          __delay_cycles (200);
          spi_tx(var8bit2);
          __delay_cycles (200);
          spi_tx(var8bit1);
          __delay_cycles (200);
      }
}

//*************SPI Receive****************
int spi_rx()
{
   uint8_t Data;
   spi_tx(0x00);            //send dummy data
   __delay_cycles (200);
   // Wait till a character is received
   // while (!(EUSCI_B0->IFG & EUSCI_B_IFG_RXIFG));
   Data = EUSCI_B0->RXBUF;  // Move data to a temporary buffer
   // Clear the receive interrupt flag
   // EUSCI_B0->IFG &= ~EUSCI_B_IFG_RXIFG;
   return Data;
}

//*****************function to single read internal resister**********//
int ReadRegister(uint8_t R_address,int N_OF_Byte)
{
   /* local variable declaration */
   int var32bit1,var32bit2,var32bit3;
   spi_tx(R_address);
   __delay_cycles (200);
   if(N_OF_Byte==1)
    {
       var32bit1 = spi_rx();
       return var32bit1;
    }
   else if(N_OF_Byte==2)
    {
       var32bit1=spi_rx();          // higher byte
       __delay_cycles (200);
       var32bit2=spi_rx();          // lower byte
       var32bit1=var32bit1<<8;
       var32bit1=var32bit1|var32bit2; // masking into 16 bit data
       return var32bit1 ;
    }

       var32bit1=spi_rx();   //higher byte
       __delay_cycles (200);
       var32bit2=spi_rx();   //middle byte
       __delay_cycles (200);
       var32bit3=spi_rx();   //lower byte
       var32bit1=var32bit1<<8;
       var32bit2=var32bit1|var32bit2;
       var32bit2=var32bit2<<8;
       var32bit3=var32bit2|var32bit3; //masking into 24 bit data
       return var32bit3;

}
//******************Read AD7730 Data*******************//
int ReadData()
{
    /* local variable declaration */
    int var32bit1,var32bit2,var32bit3;
    var32bit1=spi_rx();
    __delay_cycles (200);
    var32bit2=spi_rx();
    __delay_cycles (200);
    var32bit3=spi_rx();
    // data mapping
    var32bit1=var32bit1<<8;
    var32bit2=var32bit1|var32bit2;
    var32bit2=var32bit2<<8;
    var32bit3=var32bit2|var32bit3;
    return var32bit3;
}

void main(void)
{

      STATUS_Result1 = ReadRegister(COM_READ_STATUS_REG_CMD,1);            // read DAC Register default value
        __delay_cycles (2000);
}