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3

Your suspicion seems to be correct and your SPI clock settings are incorrect. It can be observed in the logic analyzer's image that the data changes on rising edge and stable on the falling edge. If you check the SPI timing diagram in the datasheet of the RC522. You can see that the clock is LOW before the communication, the data is sampled on the rising ...


3

After a long night I figured out what to do. This PDF, Design of MF RC500 Matching Circuits and Antennas (alternative source), has a detailed info about how to implement what I wanted. This is the image of the circuit I implemented, just needed to change some values of caps, but all near to the ones in the image. Worked perfectly.


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Single byte transaction on SPI bus usually don't allow the slave to respond anything back. Use the protocol required by the chip, like sending a command and transferring response back during a single transaction defined by CS being low.


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This happens when Arduino fails to communicate with your RFID reader. And that happens only when you blindly code something and do something else with circuit connections. You need to recheck these connections and make sure that it's consistent with what you defined in the code, and you are ready to go. SCK of RFID --> SCK of Arduino SDA --> SS (SDA, if ...


1

I will share my experience in which I had confronted with similar situation. I had to program about 24 SPI flash memories using just in master card. The setup was like this. A huge mother board. Several daughter cards were connected to it. Almost all the daughter cards had two FPGA and one DSP on it.. And both FPGA and DSP had dedicated SPI flash memories ...


1

A quick review shows that the Lant has complimentary design (first sentence on P.81 of the data-sheet). This is also true for a coil antenna such as the one you found from Molex. Short answer: Yes. Not as short: You should verify antenna parameters to understand whether you need to tune the antenna to your reader. The typical application example shows there ...


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It‘s not so easy to calculate Ra, although a close approximation of Ra is the copper dc resistance Rdc of the coil. The reason why Ra is not exactly Rdc is that at 13.56 MHz frequency, there‘s a thing called skin effect which drives the current from copper center to the copper surface and thus increases the resistance. Best thing to do is to measure the ...


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Here's 65 pages that describes all the details https://pubweb.eng.utah.edu/~mlewis/ref/NFC/AN1445.pdf try a better question.


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The SPI can work at 2 meters just fine, although at reduced speed. If you do not absolutely need maximum possible clock you can wire your modules and gradually increase speed to find out error-free maximum. As a side note, SPI is not the best protocol to use off-board when you have multiple slaves, because wiring CS lines quickly makes it cumbersome. Using ...


1

Because MFRC522 does not support Card emulation mode, When you put both PCD chips in writer mode across each other(Phone and RC522), generated field by the phone may damaged the RC522, but any way there is a version register in MFRC522 chip, try to read this register,if it was not returned successfully,means your rc522 is damaged.


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The anticollision for Mifare Type technology is capable of selecting as much transponders as the UID length is. For a 7 Byte Type UID (E.g. Desfire) there could be 256^7 tags selected. Here You find the reference for this: https://www.nxp.com/docs/en/application-note/AN10833.pdf Because of power Limitation, practically you can not read out more than 5-10 ...


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RFID tags have a working frequency (RFID-RC522 is 13,56MHz) and protocol RFID-RC522 can read Mifare tags. Most likely problems: - The RFID scanned uses another frequency (125kHz for example). - The RFID scanned uses a different protocol. There are different RFID tags, frequencies and protocols. There is no one size fits all.


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There is no read back verification. The relevant parts of Mifare_Write(): // Step 2: Transfer the data result = PCD_MIFARE_Transceive(buffer, bufferSize); // Adds CRC_A and checks that the response is MF_ACK. if (result != STATUS_OK) { return result; } return STATUS_OK; The data is merely transferred to the reader's FIFO and then an ACK is expected ...


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It would seem that the antenna matching filter is improperly designed, resulting in the transfer of insufficient power to boot a DESFIRE card from one of these cheap eBay modules. According to the links I posted above, it seems that a few people have successfully modified the cheap MFRC522 boards to successfully communicate with DESFIRE cards, by replacing ...


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