Update README.md

README.md

+Reads out serial numbers of nfc tags (if available) and prints them out
+via usb keyboard emulation.
 
+## Requirements
 
-### Considerations
+### Hardware
 
-- The Keyboard.h library must be imported via the library manager first (it is a native arduino library) to use it as a USB-HID
-- It can be a nightmare to setup RFID stuff
+- Arduino Leonardo (has SPI and Keyboard emulation support).
+- RFID-Reader "MFRC522" (library and pins: https://github.com/ljos/MFRC522)
+- Some small wires
+- USB data capable cable
+- 2 LEDs or a beeper or whatever for "card read" feedback.
+- Maybe a box to hold everything together
 
+### Software
 
-### Hardware
+- Arduino IDE
+
+
+## Misc
 
-- Arduino Pro Micro (cheap chinese, 5V ones)
-  - Pinout: https://cdn.sparkfun.com/r/600-600/assets/9/c/3/c/4/523a1765757b7f5c6e8b4567.png
+Leonardo-Pinout:
+![](Ardunio_leonardo_pinout.jpg)