Problem communicating with ADS1259 using MSP430 SPI

Other Parts Discussed in Thread: ADS1259, CC2500, MSP430F5508

Hi,

I am using the MSP430 in the ez430-RF2500 development kit to communicate with an ADS1259 via SPI.

I am trying to initialize the ADC with the following Code Composer code, but it doesn't seem to work. The MSP430 gets stuck during "while (!(IFG2 & UCB0RXIFG));" as if it can't receive anything.

Notes:

-The SPI is shared with the CC2500 radio, so it has to be disabled first as shown in the code.

-The ADC's SPI CS pin is connected to MSP430's P4.4 GPIO.

-After the communication, the ADC SPI is disabled and the radio SPI is re-enabled.

-I am assuming that "UCB0CTL0 = b10101001" for the ADC.

=======

  char junk;
   
    P3OUT |= b00000001; // turn off radio SPI
    UCB0CTL1 |= UCSWRST; // set SPI to ADC's SPI protocol
    UCB0CTL0 = b10101001;
    UCB0CTL1 &= ~UCSWRST;
    P4OUT = b11101111; // P4.4 is set low, ADC SPI is on

// stop read data continuous mode
  while((IFG2 & UCB0TXIFG) == 0);
  UCB0TXBUF = b00010001;
  while (!(IFG2 & UCB0RXIFG)); //MSP430 seems to get stuck here
  junk = UCB0RXBUF;
         
  // specify address to be CONFIG1
  while((IFG2 & UCB0TXIFG) == 0);
  UCB0TXBUF = b01000001;
  while (!(IFG2 & UCB0RXIFG));
  junk = UCB0RXBUF;
 
  // write to only 1 register
  while((IFG2 & UCB0TXIFG) == 0);
  UCB0TXBUF = b00000000;
  while (!(IFG2 & UCB0RXIFG));
  junk = UCB0RXBUF;
 
  // write register, set to use internal reference
  while((IFG2 & UCB0TXIFG) == 0);
  UCB0TXBUF = b00000000;
  while (!(IFG2 & UCB0RXIFG));
  junk = UCB0RXBUF;

  P4OUT = b00010000; // P4.4 is set high, ADC SPI is off
  UCB0CTL1 |= UCSWRST; // set SPI to radio's SPI protocol
  UCB0CTL0 = b10101001;
  UCB0CTL1 &= ~UCSWRST;
  P3OUT &= b11111110; // turn on radio SPI

======

Thank you very much for your help!

David