Serial.begin(9600) // Serial port baud rate Lcd.begin(16, 2) // set up the LCD's number of rows and columns:ĭigitalWrite(tachPin, HIGH) // turn on pull-up resistor initialize the LCD library routine with the numbers of the interface pins Unsigned int an0=0 // Variables for sending data to PC Unsigned long val // Working variable to hold the accumulated value Int sampletime=40 // Number of sample to average-out sampling values Int max_rpm=4800 // max rpm at 100% PWM outputīoolean auto_manual=1 // setpoint manual or from pot Unsigned long duration // time duration between tachometer pulses Int sensorValue // variable to store the value coming from the sensor Int sensorPin = A2 // analog input 0 for the potentiometer Int fanPin = 8 // fan drive connected to digital pin 11 Int tachPin = 6 // fan tachometer connected to digital pin 8 complete set of data over the serial port. If this is defined it prints out the FPS that we can send a Running a real-time graph under Processing software. Setpoint for speed is read from a potentiometer.

This sketch use PID controller to control PC fan speed and display result on a LCD. Not trying to hack the thread!! I am just pulling out my hair! I have hooked up the fan as per std and I can't get the Arduino to control the speed.

Download 4 pin fan pinout