You can read the first part of this blog here
, and the second part here
Research (or mucking about with stuff)
The first job was to buy a Pi screen and fingerprint scanner. I already had a Pi kicking around looking bored. A quick session on the interweb saw me securing a screen from Pimoroni
and GT-511C3 finger print scanner from Proto-Pic
The Finger Print Scanner is ideal. It is a self-contained unit that stores the fingerprint templates locally, all you need to do is ask it for the unique ID of the finger print on the scanner. This can then be cross referenced to a person. It connects via a serial connection (0-3.3V rather than 0-12V of standard RS-232) which is ideal for connecting to a Pi or Arduino UART. There was a cheaper version but that could only store 20 fingerprints, this model can store 200, which is more than we should ever need. The only problem was there were none in stock, but that was OK because Proto-Pic said they could get more stock within a week.