Hello guys, I'm trying to use a RFID-RC522 Rfid reader on a Arduino Uno WiFi Rev2 board. I searched on the internet about the SPI pins on this board but haven't been able to find a proper pinout schematic.
For information, my pins are connected like this : SDA-SDA, SCK- ICSP pin 3 , MOSI-ICSP pin 2, MISO- ICSP pin 1, IRQ- none, GND-GND, RST-DP9, 3.3V-3.3V.
Btw, just tested the rfid module on an MKR WiFi 1010 Board and it worked... I guess the problem is the SPI pins on the WiFi Rev2 board
Can you provide a link to the board?
Here you go mate! Tanks a lot for the fast reply
UNO WiFi Rev2 | Arduino Documentation | Arduino Documentation
RC522 RFID Module Pinout, Interfacing with Arduino, Applications (microcontrollerslab.com)
Yeah... that's the Uno doco champ.
The docs for this would be more useful...
RC522 RFID Module Pinout, Interfacing with Arduino, Applications (microcontrollerslab.com)
There it is...
I guess the SPI pins on the Uno WiFi Rev2 are on the ICSP pins, but I've tried both wirings (ICSP and digital pins) and none of them worked...
So you wired things exactly as shown in that tutorial... and used the tutorial code.. and it didn't work?
Yep ! that's what I did
https://docs.arduino.cc/static/d9043827f055a201be10101328efda18/schematics.pdf
It shows you exactly what and where the SPI pins are 
Your topic has been moved to the dedicated section for the Arduino WiFi Rev2
SCK and MISO look OK, but MOSI should be on pin 4.
and "SDA" (which is "SS" for SPI purposes) should probably connect to pin 10, and not the SDA pin of the Arduino. (apparently the RFID module supports several communications protocols, so that the pin labeled "SDA" can be either SDA (if using I2C), RXD (if using UART), or SS (if using SPI.) Are you sure you want to use SPI? It almost seems the least appropriate for something like an RFID reader. (But I didn't see info in the tutorial you linked for using the other methods 
))
The RFID-RC522 Rfid reader is 3.3V device, maybe it's already damaged.
Thank you a lot for your reply, but I 'm 100% sure that it's not damaged, I've just oppened it's package today and hooked it up to the 3.3V pin. So I guess there isn't any problem...
How did you make CS, SCL and MOSI 3.3V?
I doubt the I/O pins are official 5V tolerant.
Thank you a lot for your explaination, will try it on the Uno WiFi Rev2 board later 
Currently working on the same project but on an MKR WiFi 1010 board.
Thank you for this detailed schematic, that helped me a lot.
Are they supposed to only work on 5V? I'm currently using the same RFID reader on an MKR WiFoi 1010 Board and it works just fine on 3.3V
The RF chip does not like anything above 3.3V plus a diode drop on any of its pins,
at least that would be the behavior of most 3.3V devices.
Level shifters solve that problem.
Didn't know thank's for the info, but the RFID reader seems just fine... As said before it works just fine on the MKR WiFi 1010
The MKR is probably a 3.3V device?
