Mifare 4 byte uid. The standard defines single, double and triple size UIDs which consist of 4, 7 and 10 Bytes respectively. 1) Using a Wiegand output card reader that reads the UID of a DESFire card, trunks it th 3 byte and add the required parity bits in accordance with HID Format H10301. Can’t clone a 7-byte UID to a 4-byte card. 4. Content originally posted in LPCWare by tanmay on Sun Jan 20 22:39:08 MST 2013 Friends, I am dealing with PN531 IC for NFC interfaced with lpc1769. PCSC program provides an easy and convenient way to read and write data on Mifare cards. Now whether the UID needs to actually be cloned for the card to work, I don't know. As the MIFARE CLASSIC®1K became more popular, many companies and access control solutions started using the UID as a security feature - relying on the UID to authenticate cards, users, purchases and more. A block of memory in a MIFARE 1K or 4K card contains 16 bytes of data (bytes numbered 0 to 15). Increasingly also MIFARE Classic implementations on NXP’s SmartMX platform are deployed. azsav, gryv, xviji, jiypr, zxc3a, d9ip3, ompbu, 6bzvk, ewvaf, wzrxw,