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+# Arduino Mega RFID-RC522 wiring
+
+## Introduction
+
+**NB! RFID-RC522 requires only 3.3 V DC input voltage. Never connect it to 5V input.**
+
+<div class=pagebreak></div>
+
+## Wiring illustration
+
+![arduino-mega-rfid-rc522-wiring.png](arduino-mega-rfid-rc522-wiring.png)
+
+## Wiring table
+
+| Signal | ATMega2560 port and pin | Arduino Mega 2560 pin | 5V to 3V converter | RFID-RC522 | Wire colour in illustration |
+| --- | --- | --- | --- | --- |  --- |
+| Slave select | PORTB 0 | 53 | - | SDA | White |
+| SPI clock | PORTB 1 | 52 | - | SCK | Orange |
+| Master out slave in | PORTB 2 | 51 | - | MOSI | Green |
+| Master in slave out | PORTB 3 | 50 | - | MISO | Yellow |
+| RF522 reset | PORTL 0 | 49 | - | RST | Brown |
+| Ground | GND | GND | GND | GND | Black |
+| 5 V DC | - | 5V | VIN | - | Red |
+| 3,3 V DC | - | - | VOUT | 3.3 V | Red |
+
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