13,56 MHz RFID in software

[Tost]

Some people emulated 125 kHz-RFID-tags with just a coil connected to a small 8-bit µC. Does that theoretically work for 13,56 MHz Mifare-Classic in a similar way? May be with some additional passives to realize the load modulation? If I get it correctly there are much more clock cycles available compared to the 125 kHz version. The 847.5 kHz subcarrier may generated by  hardware pwm.

[NoNRG]

13.56 MHz is used for NFC communication. You might try researching examples using NFC.

Here's a quick example of automatic impedance matching different antennas for use with 13.56 MHz.
http://www.nfc-research.at/fileadmin/papers/2008/14/2008_07_23_csndsp08.pdf

[dpavlin]

It dies indeed work for 13.56 MHz Mifare tags. Chameleon project at http://sourceforge.net/p/chameleon14443/home/Home/ implementats it using AVR to create emulator for ISO 14443 contactless smartcards. As additional bonus, it's open hardware project together with eagle schematics, board and documentation.

[Tost]

Great! That was exactly was I looking for. Thanks a lot dpavlin.