AD5940 Setup Help

Hi all,

I am in the process of setting up the AD5940 to interface with an electrochemical sensor. However, I would like to first test that the ADC is working in principle by configuring it to read from the internal temperature sensor.

Below is how I am currently configuring the registers, but I am not able to read the default raw temperature data. Could someone advise what I might be doing wrong?

read_adc() is being called once a second

void AD5940_setup(void)
{
// DEvice INT as per data sheet.
AD5940_WriteRegister(0x00000908, 0x02C9, 1);
AD5940_WriteRegister(0x00000C08, 0x206C, 1);
AD5940_WriteRegister(0x000021F0, 0x0010, 1);
AD5940_WriteRegister(0x00000410, 0x02C9, 1);
AD5940_WriteRegister(0x00000A28, 0x0009, 1);
AD5940_WriteRegister(0x0000238C, 0x0104, 1);
AD5940_WriteRegister(0x00000A04, 0x4859, 1);  // Power mode key part 1
AD5940_WriteRegister(0x00000A04, 0xF27B, 1);  // Power mode key part 2
AD5940_WriteRegister(0x00000A00, 0x8009, 1);  // PWRMOD register
AD5940_WriteRegister(0x000022F0, 0x0000, 1);

//Set up for 4 pin gas sensor
 AD5940_WriteRegister(0x00002120, 0x1A68B, 1); //LPDACDAT0  BIAS 0V  (VZERO0 and VBIAS0) both set to 1.1 V. 
 AD5940_WriteRegister(0x00002128, 0x00, 1); //LPDACCON0 
 AD5940_WriteRegister(0x000020EC, 0x1AE0, 1);  // Set LPTIACON0: RTIA=160k, RLOAD=30?, TIAPDEN,PAPDEN
 AD5940_WriteRegister(0x000020E4, 0x302C, 1);// LPTIASW0 SWitches 
 
 //Setup for Tempearture reading 

AD5940_WriteRegister(0x2000,(1 << 12), 1);  // Enables sensor + starts conversion
// Select temperature sensor as ADC input
AD5940_WriteRegister(0x21A8, 0xB0B, 1); // ADCCON: MUXP = TEMPSENSP, MUXN = TEMPSENSN
AD5940_WriteRegister(0x2000, (1 << 8) | (1 << 12) |(1 << 13), 1);  // Enables sensor + starts conversion
// Start ADC conversion
AD5940_WriteRegister(0x000021F0, 1, 1);  // Start 1 conversion
}

void read_adc(void)
{
    
 temp_raw = AD5940_ReadRegister(0x2084, 1);  // TEMPSENSDAT
 temperature_ic = ((float)temp_raw / (1.0f * 8.13f)) - 273.15f;
    // (Optional) Store or print the result
    
AD5940_WriteRegister(0x2000, (1 << 8) | (1 << 12) |(1 << 13), 1);  // Enables sensor + starts conversion
AD5940_WriteRegister(0x000021F0, 0x0010, 1);  // Start 1 conversion

}