Arduino reads AD7780 24bit ADC

Projects Networking, Protocols, and Devices
6

Try changing the for loop to this:

  uint32_t adc_read = 0;
  for(int i=0; i< 32; i++)
  {
    digitalWrite(AD7780_SCK, LOW);
    delayMicroseconds(10);
    digitalWrite(AD7780_SCK, HIGH);
    if(a = digitalRead(AD7780_MISO)) {
      adc_read |= 1;
    }
    adc_read <<= 1;
    delayMicroseconds(10);
  }
// If the status byte is sent first use this
  uint8_t stat;
  stat = adc_read >> 24;
  adc_read &= 0xffffff;
// If the ADC reading is sent first use this
  uint8_t stat;
  stat = adc_read & 0xff;
  adc_read >>= 8;

The datasheet doesn't really say whether the status byte is sent before or after the ADC reading so I've added code for both possibilities. Pick whichever one is correct.

Pete