This document shows the use of UIDs in contactless smartcard systems. It indicates recommendations about the Random ID, mixed use of 4 byte and 7 byte UIDs in the same system, and it describes the options how to upgrade 4 byte UID systems to accept 7 byte UID smart cards.
非常有用的资料，谢谢分享。目前正在研究mifare1系统如何处理7字节的UID问题