/*
  Blink
  Turns on an LED on for one second, then off for one second, repeatedly.

  Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO 
  it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN takes care 
  of use the correct LED pin whatever is the board used.
  If you want to know what pin the on-board LED is conn
  ected to on your Arduino model, check
  the Technical Specs of your board  at https://www.arduino.cc/en/Main/Products
  
  This example code is in the public domain.

  modified 8 May 2014
  by Scott Fitzgerald
  
  modified 2 Sep 2016
  by Arturo Guadalupi
*/

#include <Arduino.h>
#include <Adafruit_TinyUSB.h> // for Serial

uint32_t baud_test[] = {
  1200,
  2400,
  4800,
  9600,
  14400,
  19200,
  28800,
  31250,
  38400,
  56000,
  57600,
  76800,
  115200,
  230400,
  250000,
  460800,
  921600,
  1000000
};

uint32_t baud_expected[] = {
  UARTE_BAUDRATE_BAUDRATE_Baud1200,
  UARTE_BAUDRATE_BAUDRATE_Baud2400,
  UARTE_BAUDRATE_BAUDRATE_Baud4800,
  UARTE_BAUDRATE_BAUDRATE_Baud9600,
  UARTE_BAUDRATE_BAUDRATE_Baud14400,
  UARTE_BAUDRATE_BAUDRATE_Baud19200,
  UARTE_BAUDRATE_BAUDRATE_Baud28800,
  UARTE_BAUDRATE_BAUDRATE_Baud31250,
  UARTE_BAUDRATE_BAUDRATE_Baud38400,
  UARTE_BAUDRATE_BAUDRATE_Baud56000,
  UARTE_BAUDRATE_BAUDRATE_Baud57600,
  UARTE_BAUDRATE_BAUDRATE_Baud76800,
  UARTE_BAUDRATE_BAUDRATE_Baud115200,
  UARTE_BAUDRATE_BAUDRATE_Baud230400,
  UARTE_BAUDRATE_BAUDRATE_Baud250000,
  UARTE_BAUDRATE_BAUDRATE_Baud460800,
  UARTE_BAUDRATE_BAUDRATE_Baud921600,
  UARTE_BAUDRATE_BAUDRATE_Baud1M
};

uint32_t compute_baud_reg(uint32_t baudrate)
{
  // details here: https://devzone.nordicsemi.com/f/nordic-q-a/391/uart-baudrate-register-values
  // 2^32 / 16000000 = 268.43f.
  const double regValue = 268.43f*(double)baudrate;
  const uint32_t nrfBaudRate = ((uint32_t)regValue + 0x800) & 0xFFFFF000;

  return nrfBaudRate;
}

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(LED_BUILTIN, OUTPUT);

  while(!Serial) delay(100);
  Serial.println("Baud test");
  delay(100);

  for(uint8_t i=0; i < sizeof(baud_test)/sizeof(baud_test[0]); i++)
  {
    uint32_t value = compute_baud_reg(baud_test[i]);
    Serial.printf("Baud: %u, Expected: %08X, Actual: %08X ... ", baud_test[i], baud_expected[i], value);
    if ( value != baud_expected[i] ) {
      Serial.println("FAILED");
    }else
    {
      Serial.println("OK");
    }
  }
}
     
// the loop function runs over and over again forever
void loop() {
  digitalToggle(LED_BUILTIN); // turn the LED on (HIGH is the voltage level)
  delay(1000);                // wait for a second
}