Mifare RFID off-the-shelf reader library with card authentication/key

Projects General Guidance
1

Hi All
I've been doing a bit of research on RFID, in particular around Mifare / 13.56mhz cards. I'm still fairly new to this so please excuse any 'duh' moments.

I can find plenty of information in regards to 125khz cards including hooking up commercially available readers with wiegand connections (D0, D1, Vcc and Gnd connection) along with plenty of different options components.

I am wanting to use something a bit more secure than the normal 125khz cards and think what I want is Mifare cards that require sector-based authentication keys before releasing the card's data.

I can find information about MFRC522 based arduino gear which I have ordered to test out, but I want to use something commercially available and easy to install etc. similar to the below:

These readers claim to have a wiegand style interface (D0/D1) pins but I'm not sure if this is going to work as all the libraries seem to be based on SPI and I cannot find any libraries, adapters/converters or anything that appear to work with this style of reader.

Basically I want to be able to write some cards with a custom key and then (hopefully easily - I'm still new to Arduino etc.) use a reader similar to the ebay job above to read them using something similar to this: NFC Success! - Interfacing with Mifare - Interfacing w/ Software on the Computer - Arduino Forum

This is so that I can have cards that are at least somewhat secure and protected from (at least easy) cloning so that not just anyone can read them.

Can anyone point me in the right direction? Please note that I'm still quite new to this :slight_smile:

Thanks

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I'm not sure what you want to achieve. When your cards are user programmable, everybody can clone them using the same programmer. As I understand it, the security resides in the manufacturing process (card programming), not available to users.

For the interface part, you have to convert the pulses on the data lines into bit patterns. The logical AND of both lines can be used for SCLK, two diodes can do that. The D0 or D1 line becomes the MOSI input of an SPI slave. This way you can use the supplied SPI libraries with your reader device.

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These readers claim to have a wiegand style interface (D0/D1) pins

That is an output only, you can not program anything by writing into a Weagand interface. If the reader has only a Wegand output then you are not able to write onto your card with it.