Abstract: In the production of smart IC cards, in order to facilitate the use and query of the system, most systems need to laser engrave the card's UID (commonly known as internal code) on the card surface. The following are some common internal code formats under analysis. Such as: Mifare® 1k S50 card, sector 0, block 0 data: 2A83155EE288040047C129D24D000607 Normally . we can see clear like ...