DAC81416-08EVM: DAC81416 not outputting expected value when used with Arduino DUE, but gives expected output when using USB2ANY connector and the EVM software

Tool/software:

Jumper Settings:

J10 - 1-2

J2 - OPEN

J3 - OPEN

J11 - 1-2

J9 - 1-2

J7.1 - OPEN

J7.2 - OPEN

J7.3 - GND

J7.4 OPEN

J7.5 - 5V

J7.6 - GND

J7.7 - 12V

Using Default SPI pins on Arduino DUE

The code used:

#include <SPI.h>

// Define SPI settings
#define DAC_CS_PIN 10       // Chip Select (CS) pin for DAC
#define SPI_CLOCK 1000000   // SPI Clock Speed: 1 MHz
#define SPI_MODE SPI_MODE1  // SPI Mode 1 (CPOL=0, CPHA=1)
// #define RESET 9



void setup() {

  delay(5000);
  // Start Serial for debugging
  Serial.begin(9600);
  Serial.println("Initializing DAC81416...");

  // pinMode(RESET, OUTPUT);
  // digitalWrite(RESET, HIGH); // Set reset alwats high


  // Initialize SPI
  SPI.begin();

  // Configure the CS pin
  pinMode(DAC_CS_PIN, OUTPUT);
  digitalWrite(DAC_CS_PIN, HIGH); // Set CS high (inactive)

  // Start SPI transaction
  SPI.beginTransaction(SPISettings(SPI_CLOCK, MSBFIRST, SPI_MODE));

    // Enable SPI communication
// writeSPI(0X00, 0x0001); // Step 0: Enable SPI communication (SPICONFIG register) 0x030004

  // // Minimum SPI commands to configure and verify the DAC
  writeSPI(0x03, 0x0A04); // Step 1: Power up the DAC81416 (SPICONFIG register) 
   writeSPI(0x04, 0x4F00); // Step 2: Use internal reference (GENCONFIG register)
   //writeSPI(0x06, 0x0000); 
  writeSPI(0x09, 0x0000); // Step 3: Power up all DAC channels (DACPWDWN register)
  //writeSPI(0x0D, 0x0000); // Step 4: Set DAC0-3 voltage range to 5V (DACRANGE0)
  //writeSPI(0x05, 0xFFFF);
  writeSPI(0x10, 0xFFFF); // Step 5: Write full-scale value to DAC0 (DAC0_DATA)
  // writeSPI(0x01, 0x8100);
  // writeSPI(0x01, 0x8100);
  Serial.println("DAC Configuration Complete. Check Output Voltage.");
}

void loop() {
  // // Optional: Write a new value to DAC0 periodically for testing
  // writeSPI(0x10, 0xFFFF); // Write max-scale value to DAC0
  // delay(1000);

  // writeSPI(0x10, 0x0000); // Write min-scale value to DAC0
  // delay(1000);

  // writeSPI(0x10, 0x8000); // Write mid-scale value to DAC0
  delay(1000);
}

// Function to write a 24-bit SPI frame
void writeSPI(uint8_t regAddress, uint16_t data) {
  digitalWrite(DAC_CS_PIN, LOW);   // Pull CS low to start communication
  SPI.transfer(regAddress);        // Send 8-bit register address
  SPI.transfer16(data);            // Send 16-bit data
  digitalWrite(DAC_CS_PIN, HIGH);  // Pull CS high to end communication
}