The project involves a smart cafe in which clients can vote for the background music (and other features) only by placing their 
 cups on a certain position on the table.  
 This code is used by a Raspberry Pi, with two NFC readers connected to it via SPI.
 The NFC readers are placed under a table and allow users to vote, with a NFC tag place under a cup, for either classical or rock music.
 The NFC readers share the same MISO, MOSI, CLK, which means that they need to be multiplexed. 
 To do that the RST and CS lines in the SPI software configurations are switched to access the two boards.
 The main program is readID.c, which uses nfc.c to interface with the NFC boards, extract information, group it together and send it 
 via a named pipe to mosquitto_client.c, which splits the data and sends it out to the network via MQTT messages.
 This was required as the wiringPi libraries and the mosquitto library were not compatible.