// FanSpeed example from https://github.com/PaulStoffregen/TimerOne/blob/master/examples/FanSpeed/FanSpeed.ino
//

#include <TimerOne.h>

// This example creates a PWM signal with 25 kHz carrier.
//
// Arduino's analogWrite() gives you PWM output, but no control over the
// carrier frequency.  The default frequency is low, typically 490 or
// 3920 Hz.  Sometimes you may need a faster carrier frequency.
//
// The specification for 4-wire PWM fans recommends a 25 kHz frequency
// and allows 21 to 28 kHz.  The default from analogWrite() might work
// with some fans, but to follow the specification we need 25 kHz.
//
// http://www.formfactors.org/developer/specs/REV1_2_Public.pdf
//
// Connect the PWM pin to the fan's control wire (usually blue).  The
// board's ground must be connected to the fan's ground, and the fan
// needs +12 volt power from the computer or a separate power supply.

const int fanPin = 9;
const int dataPin = 5;
void setup(void)
{
  Timer1.initialize(250);  // 40 us = 25 kHz
  Serial.begin(115200);
  pinMode(2,OUTPUT);
}

void loop(void)
{
  // slowly increase the PWM fan speed
  //
  if (1) {
    for (float dutyCycle = 10.0; dutyCycle < 100.0; dutyCycle+=80) {
    //  Serial.print("PWM Fan, Duty Cycle = ");
    //  Serial.println(dutyCycle);
      Timer1.pwm(fanPin, (dutyCycle / 100) * 1023);
      digitalWrite(2,!digitalRead(2));
      delay(10);
    }
  }
  //dutyOut(9,4,LSBFIRST,0xBB);
  delayMicroseconds(200);

}

void dutyOut(uint8_t dataPin, uint8_t ledPin, uint8_t bitOrder, uint8_t val)
{
  uint8_t i;
    digitalWrite(2,HIGH);

  for (i = 0; i < 8; i++)  {
    if (bitOrder == LSBFIRST) {
      digitalWrite(ledPin, val & 1);
      Timer1.pwm(dataPin,10 * (val & 1));
      val >>= 1;
    } else {
      digitalWrite(ledPin, (val & 128) != 0);
      Timer1.pwm(dataPin,1000 * ((val & 128) != 0));
      val <<= 1;
    }
    delayMicroseconds(1);
  }
    digitalWrite(2,LOW);

}