I have an fps gt-511c1r fingerprint sensor module. I want to know whether i can run it using teensy 3.0 or above? I have tried it successfully using arduino uno.

EDIT: I have uploaded the fps blink sketch on the teensy 3.2 successfully, but the fingerprint scanner is not responding. Here is the code:-
#include "FPS_GT511C3.h"
#include "SoftwareSerial.h"

     // Hardware setup - FPS connected to:  
     //   digital pin 0(arduino rx, fps tx)  
     //   digital pin 1(arduino tx, fps rx)  

     FPS_GT511C3 fps(0, 1);

     void setup()
         fps.UseSerialDebug = true; 

     void loop()
        // FPS Blink LED Test

connected fps tx to teensy rx(pin 0),
fps rx to teensy tx(pin 1),
fps vcc to 3.3v teensy,
fps gnd to teensy gnd.

  • Have you tried it on a teensy?
    – Majenko
    Commented Jul 30, 2016 at 9:31
  • As something with a UART interface there should be very little hardware dependence - presumably the hardware serial library on the Teensy works. You might avoid or re-work sketches that try to use software serial though, since the Teensy has plenty of hardware serial ports. Commented Jul 30, 2016 at 16:36
  • Your library looks to be using software serial internally, that is probably not what you want on a Teensy where you have plenty of real UARTs. Or at least, if you are going to do it that way, make sure you use a version that works on the Teensy ina way that works on the Teensy. Some web search research is in order. Commented Aug 3, 2016 at 14:14
  • Please can u guide me as to how to disable the software serial? Commented Aug 3, 2016 at 18:55

1 Answer 1


The GT-511C1R is a 5V device. The Teensy 3.0 is a 3.3V device. You will require some level shifting as you would with any 3.3V Arduino connecting to a 5V device.

Besides that, yes, the Teensy 3.0 is more than capable of working with the fingerprint scanner. Will the software work? Most likely, but only trying it will confirm that.

  • Thank you very much:) i'll definitely try n tell if it works.. Commented Jul 30, 2016 at 13:25
  • What makes you say that "The GT-511C1R is a 5V device" ? The data sheet says "DC 3.3~6v" Commented Jul 30, 2016 at 16:35
  • The spark fun site says 5v.
    – Majenko
    Commented Jul 30, 2016 at 16:47
  • I tried a simple blink code for the fingerprint scanner. It uploaded successfully but there is no response from the scanner:( I uploaded the same code on the arduino uno and powered the scanner with 3.3v and it works. So why isnt it working with teeny?? Even though the sketch is uploaded? Commented Aug 3, 2016 at 10:44
  • Because you did something wrong, obviously. I have no idea what you did, though, so I don't know what part of it was done wrong.
    – Majenko
    Commented Aug 3, 2016 at 10:46

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