#include <SPI.h>
#include <Arduino.h>
//---- Deklaration of the used pins for SPI0 ----
const uint8_t SPI_MISO = 16;
const uint8_t SPI_CS   = 17;
const uint8_t SPI_SCK  = 18;
const uint8_t SPI_MOSI = 19;

SPISettings parSPI(2000000, MSBFIRST, SPI_MODE0);
 
void setup() {
  Serial.begin(115200);
  while(!Serial) delay(10);
  delay(1000);
  Serial.println("SPI-Test with MCP3008");
  //---- Define the used SPI pins -------
  bool xOK = SPI.setRX(SPI_MISO);
  xOK &= SPI.setTX(SPI_MOSI);
  xOK &= SPI.setSCK(SPI_SCK);
  xOK &= SPI.setCS(SPI_CS);
  if (xOK)
    SPI.begin(true);  // OK -> run
  else
  { //---- Error with setXX(...) -----
    Serial.println("Fehler bei serXX");
    pinMode(25, OUTPUT);
    while(true)
    { //---- signal the error with integrated LED 
      digitalWrite(25,HIGH);
      delay(250);
      digitalWrite(25,LOW);
      delay(250);
    }
  }
}
 
void loop() {
  uint16_t reading = mcp3008_read(0);
  Serial.println(reading);
  delay(500);
}
 
//==== Read a value from MCP3008 =====
//     channel = # of analogue channel
//     return (analogue value)
//-------------------------------------
uint16_t mcp3008_read(uint8_t channel) {

  SPI.beginTransaction(parSPI);
  uint8_t temp = SPI.transfer(0x01);
  uint8_t msb = SPI.transfer(0x80 + (channel << 4));
  uint8_t lsb = SPI.transfer(0x00);
  SPI.endTransaction();
  Serial.printf("%d,%d,%d,",temp,msb,lsb);  // For debug only
  return ((msb & 0x03) << 8) + lsb;
}

SPI.beginTransaction(SPISettings(14000000, MSBFIRST, SPI_MODE0));

SPI_BAUDRATE 1,000,000
SPI_POLARITY 0
SPI_PHASE 0
SPI_BITS 8
SPI_FIRSTBIT MSB
SPI0_SCK Pin 6
SPI0_MOSI Pin 7
SPI0_MISO Pin 4
SPI1_SCK Pin 10
SPI1_MOSI Pin 11
SPI1_MISO Pin 8

bool setRX(pin_size_t pin);
bool setCS(pin_size_t pin);
bool setSCK(pin_size_t pin);
bool setTX(pin_size_t pin);