Problem reading data from CS5460A and ATMEGA8

[Alex Aldridge Arabaolaza]

Hi mates, i'm trying to perform some measurements using a CS5460A (Cirrus Logic) microcontroller and an ATMega8 from AVR.

Here is my initialization code for the CS5460A:

#define CONFIG_REGISTER          0x40
#define CYCLE_COUNT_REGISTER 0x4A
#define STATUS_REGISTER         0x5E
#define MASK_REGISTER             0x74


void initCS5460A(){
							   
	unsigned char temp;

	CLEARBIT(PORTD, PD_RESET);	//Give CS5460 a h/w reset (PD4 = 0)
	
	SETBIT(PORTB, PB_CLCS);		// waste some time (2.9 us?)
	SETBIT(PORTB, PB_CLCS);		// waste some time (2.9 us?)
	
	SETBIT(PORTD, PD_RESET);	//
	
	//The resistor on MS_RESET will add another delay. Need to wait some us after reset pulse before starting CS5461 comms
	SETBIT(PORTB, PB_CLCS);		// waste some time (2.9 us?)
	SETBIT(PORTB, PB_CLCS);		// waste some time (2.9 us?)
	SETBIT(PORTB, PB_CLCS);	        // waste some time (2.9 us?)
	
	tm_cs5460 = 0;
        er_cs5460 = 0;

        /*This function is used whenever CS5460A is reset so each time we need to reset the following values*/
	SETBIT(ms_flags, MS_1ST_READ);   //Used to discard first read
	CLEARBIT(ms_flags, MS_CS_RESET); //Disable reset flag (it has been already done)
	CLEARBIT(tb_flags, TB_INT_LOW);	 
        
        
        //Output initialisation sequence to CS5461 via SPI
        init_CS5460A_send_sequence();
}

void init_CS5460A_send_sequence(){

    CLEARBIT(PORTB, PB_CLCS);       //Enables SPI communication

     //Resync
    cs5460_send(0xFF);
    cs5460_send(0xFF);
    cs5460_send(0xFF);
    cs5460_send(0xFE);
    
    //soft reset
    cs5460_Write_data(CONFIG_REGISTER, 0x000080);

    
    //Resync
    cs5460_send(0xFF);
    cs5460_send(0xFF);
    cs5460_send(0xFF);
    cs5460_send(0xFE);
    
    //configure (x10 gain for current)
    cs5460_Write_data(CONFIG_REGISTER, 0x000061);
    
    //set integration period (72 clocks)
    cs5460_Write_data(CYCLE_COUNT_REGISTER, 0x000048);

     //reset all bits in status register (IC* bit ignored)
     cs5460_Write_data(STATUS_REGISTER, 0xFFFFF);

    
     //set DRDY in mask register (for INT*)
     cs5460_Write_data(MASK_REGISTER, 0x800000);

    
    //start continuous computation cycles
    cs5460_send(0xE8);
    
    SETBIT(PORTB, PB_CLCS);         //Disables SPI communication

}

After that, I try to perform some reads but the program seems to hang (it should light a LED after 20 seconds but it never lights)

This is my code to perform a read:

void cs5460_sync(){
	
	/*This functions sends the init sequence that the CS5460A needs to start operating*/
	unsigned char sync_sequence[] = {0xFF, 0xFF, 0xFF, 0xFE};
	unsigned char iterator = 0;
	
	for (iterator = 0; iterator < 4; iterator++){
		
		cs5460_send(sync_sequence[iterator]);
	}
}




unsigned long int cs5460_Read_data(char cData)
{
  char spi_data1=0,spi_data2=0,spi_data3=0;
  /* Start transmission */
  cs5460_sync();
  SPDR = cData;
  /* Wait for transmission complete */
  while(!(SPSR & (1<<SPIF)))
  spi_data3=SPDR;
  SPDR = 0xff;
  while(!(SPSR & (1<<SPIF)))
  spi_data3=SPDR;
  SPDR = 0xff;
  while(!(SPSR & (1<<SPIF)))
  spi_data2=SPDR;
  SPDR = 0xff;
  while(!(SPSR & (1<<SPIF)))
  spi_data1=SPDR;

  
  return (0x00FFFFFF & (((spi_data3*65536) & 0x00FF0000)|((spi_data2<<8) & 0x0000FF00)|(spi_data1& 0x000000FF)));
}

Do you have any idea of what could be wrong here?

Thanks in advance,

ALex