Hey folks.
I'm attempting to have an Arduino Uno control both a USB shield (with barcode scanner attached) as well as Sparkfun's RFID antenna shield combined with the SonMicro SM130.
I've done a bit of reading and think I can use one of the protocols in the title to facilitate this, but I'm not entirely sure how to go about it.
Here's a link to another thread with the code I'm using to make the USB shield receive barcode data.
http://forum.arduino.cc/index.php?topic=329069.0
Are there any resources that will make learning SPI communication simpler?