I use Arduino 1.8.9
Required library: QTRSensors by Pololu
Library can be downloaded from Tools/Manage Libraries
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Select:
Board/Arduino Nano
Processor/ATMega328p (old bootloader)
COM/What ever number device is connected to
Programmer/ArduinoISP
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Open filawinder.ino
Locate:        pinMode(12, INPUT);
Add under:    pinMode(A4, OUTPUT); //added line

Locate:        digitalWrite(12, HIGH);
Add under:    digitalWrite(A4, LOW); //added line
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Locate:        bool logOn=false;
Add under:
//added variables for filament guide v2.0
unsigned long startMillis;  //some global variables available anywhere in the program //added line
unsigned long currentMillis; //added line
const unsigned long period = 3000;  //more time will move the guide further
// end of added variables
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Locate:
void setup ()
{
Add under:
startMillis = millis();  //initial start time //added line
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Locate:
void loop ()
{
Add under:
currentMillis = millis();  //get the current "time" //added line
if (currentMillis - startMillis >= period)  //test whether the period has elapsed
  {
    digitalWrite(A4, LOW);//added line
  }
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Locate: guide_angle = (guide_angle + 1.17); }     //Move the guide +1.17 degree for 1.75mm filament
Change to:
 guide_angle = (guide_angle + 1.17);
    digitalWrite(A4, HIGH); //added line
    startMillis = currentMillis;  //IMPORTANT to save the start time of the current LED state. //added line
    }     //Move the guide +1.17 degree for 1.75mm filament
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