#include <SPI.h>
SPIClass SPI1(HSPI);

void setup() {
pinMode(4,OUTPUT);

// Reset MAX3421
digitalWrite(4,0);
delay(5000);
digitalWrite(4,1);

// Pins for clk, miso, mosi, ss
SPI1.begin (14, 32, 13, 15);
SPI1.setHwCs(true);
}

void loop() {
  SPI1.beginTransaction(SPISettings(3000, MSBFIRST, SPI_MODE0));
  SPI1.transfer16(0xA200);  // Write 00 to R20
  SPI1.endTransaction();
  delay(1000);

  SPI1.beginTransaction(SPISettings(3000, MSBFIRST, SPI_MODE0));
  SPI1.transfer16(0xA2ff);  // Write 00 to R20
  SPI1.endTransaction();
  delay(1000);
}