I am having difficulty setting up my fingerprint sensor. I'm using the library from https://github.com/sparkfun/Fingerprint_Scanner-TTL/tree/master/FPS_GT511C3 and none of the example sketches work.
I have a message printing to the serial before the fps.open() command and a message printing afterwards, but I only ever see the first message. Does this mean the arduino is stuck trying to open the scanner?
I also tried this code: http://startingelectronics.org/articles/GT-511C3-testing/ and only saw data coming back into the serial when I unplugged and reconnected the TX wire on the sensor. Nothing happens when the wire is simply left alone.