Talking to ADS8698 (18-bit ADC) over SPI I want to talk to an ADS8698 over SPI (see page 36 for details on their SPI implementation) using a Teensy 3.2. Right now I'm only getting zeros back and I feel like (perhaps wrongly) that I've followed the datasheet correctly. I believe my SPI mode is correct and, given the clock rates I'm using, I should be observing the timing constraints properly.

(1) Is there a glaring error here? I haven't coded that many SPI interfaces, so I might have a novice mistake in there.

(2) Is there existing code for a product that uses a nearly identical SPI interface to the ADS8698 (any product that has a similar timing diagram would do)?

#include &lt;SPI.h&gt;

#define USB_RATE 19200//usb transfer rate
#define SPI_CLOCK 10000000//spi clock frequency

#define CS0 10

SPISettings ADC_SPI(SPI_CLOCK, MSBFIRST, SPI_MODE1);

void setup()
{
  // disable both multiplexers
  pinMode(CS0, OUTPUT);
  digitalWrite(CS0, HIGH);
  // prepare serial protocols
  Serial.begin(USB_RATE);
  SPI.begin();
}

void read_ADC()
{
  // begin the session by taking CS0 low
  SPI.beginTransaction(ADC_SPI);
  digitalWrite(CS0, LOW);// slave select disable
  // delayMicroseconds((int) (1e6 * 20/SPI_CLOCK));// wait &gt; 16 clock cycles
  // transfer 16 bits while the ADC performs conversion
  SPI.transfer(0); // I'm not trying to set any registers, just waiting (zero is fine)
  SPI.transfer(0); // I'm not trying to set any registers, just waiting (zero is fine)
  // data should be ready, so try to read it
  Serial.println(SPI.transfer(0));
  Serial.println(SPI.transfer(0));
  // end the session by taking CS0 high
  digitalWrite(CS0, HIGH);// slave select enable
  SPI.endTransaction();
}

void loop()
{
  delay(1000);
  read_ADC();
}


The system is wired like this:
Per the Datasheet PG47

During power-up or reset, the default content of the command register is all 0's and the device waits for a command to
be written before being placed into any mode of operation.

If your still working with this I'm going to be tackling this same thing very soon, hopefully I can get it to work with DMA.
https://forum.pjrc.com/threads/34863-Teensy-CC-Dummy-Load-300W/page4