Personally, I'd have a button on the display "Swipe card" and only enter the read loop when the button was pushed.
Alternatively, put the swiper loop in a thread.
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.