Proxmark3 vs Ultralight C

There have been no secrets this week while I’ve been trying to add Mifare Ultralight C support to the Proxmark. Ultralight C cards are HF (13.56MHz) tags that are part of the Mifare family.  This week has been an interesting learning process, and it has corrected some misconceptions I had about the card.  For those interested you can follow my progress at http://www.proxmark.org/forum/viewtopic.php?id=1946.  But I will summarise my findings below: Ultralight C…