Hello everybody, how are you doing?
I'm developing a custom Arduino UNO board that includes a MIFARE RC522 chip. The communications between the ATMEGA328 and the RC522 seems to be working since the serial console is showing this:
Looking for MFRC522.
Found chip RC522 Firmware version: 0x92
But I'm not able to read any tag. I have a RC522 shield for testing and with it I can read all my tags.
I made some mistakes in the design of the PCB antenna. At the beginning I was having a gain of 230mV and 13.56 MHz, so my first impressions were that the strength of the signal was the problem, I made some cuts to the board and now the oscilloscope shows about 10.7V and 13.56 MHz (Wave.jpg). I don't have the expertise to know what is wrong with my design. I attached the eagle project. It's a little frustrating because my first attempt was using a PIC16@3.3v (white board of the Boards.jpg) and the board works but now with Arduino@5V with a shifter I have communication with the chip but I'm not able to read anything.
This is the sample code and tutorial I'm using
https://brainy-bits.com/tutorials/card-reader-with-an-arduino-rfid-using-the-rc522-module/Any suggestion is appreciated
Thanks and best regards.