Why is my fingerprint sensor not responding to my arduino code?
<p>I have bought a GT-511C1R fingerprint scanner, to work in combination with my Arduino Mega. I used this example: <a href="http://www.homautomation.org/2014/10/11/playing-with-finger-print-scanner-fps-on-arduino/" rel="nofollow">http://www.homautomation.org/2014/10/11/playing-with-finger-print-scanner-fps-on-arduino/</a></p>

<p>But when i try to blink the led using the default code which came with the library</p>

<pre><code>#include "FPS_GT511C3.h"
#include "SoftwareSerial.h"

// Hardware setup - FPS connected to:
//    digital pin 4(arduino rx, fps tx)
//    digital pin 5(arduino tx - 560ohm resistor fps tx - 1000ohm resistor - ground)
//      this brings the 5v tx line down to about 3.2v so we dont fry our fps

FPS_GT511C3 fps(4, 5);

void setup()
{
    Serial.begin(9600);
    fps.UseSerialDebug = true; // so you can see the messages in the serial debug screen
    fps.Open();
}


void loop()
{
    // FPS Blink LED Test
    fps.SetLED(true); // turn on the LED inside the fps
    delay(1000);
    fps.SetLED(false);// turn off the LED inside the fps
    delay(1000);
}
</code></pre>

<p>it doesn't do anything. On my serial monitor i get:</p>

<pre><code>FPS - Open
FPS - SEND: "55 AA 01 00 00 00 00 00 01 00 01 01"
</code></pre>

<p>but the LED of the finger scanner stays off. In combination with my Arduino Uno it does work. What can be the problem?</p>

<p>EDIT: After the answer of changing the pins, it worked just 1 time via pin 10 and 11. After removing the power, it didn't work anymore. Also not on other pins.</p>